Easy & Authentic Key Lime Slab Pie Recipe: A Zesty Dessert for Any Occasion
Experience the bright, tangy delight of Key Lime Pie in a wonderfully shareable slab pie format. This recipe features a luscious, fresh custard, bursting with the vibrant essence of Key Lime zest and juice, all baked into a perfectly flaky, from-scratch crust. Crowned with a cloud of homemade whipped cream, this Key Lime Slab Pie is not just a dessert; it’s a stunning presentation and a guaranteed way to bring a burst of sunshine and joy to any gathering or a simple day at home.
Discover the Charm of Key Lime Slab Pie
While a pilgrimage to Key West for an “authentic” slice of Key Lime Pie remains a dream for many, this Key Lime Slab Pie brings that classic Florida Keys flavor right to your kitchen. The beauty of a slab pie lies in its generous, rectangular form, making it ideal for serving a crowd at parties, potlucks, or family gatherings. It offers all the traditional zesty goodness but with a convenient, larger footprint, ensuring everyone gets a taste of this iconic dessert. It’s truly a breathtakingly beautiful dessert, reminiscent of the stunning vistas of the Florida Keys themselves—a solid reason to add this recipe to your culinary bucket list!
Now, when it comes to “authentic” Key Lime Pie recipes, many purists insist on a graham cracker crust. And while this particular recipe could easily be adapted for that, I’ve dedicated myself to perfecting my homemade, flaky pie crust-making skills. My goal is to create a crust that would make my grandma and my Aunt Carol proud. That’s why you’ll find a delightful, traditional flaky crust gracing this Key Lime Slab Pie recipe. It offers a wonderful contrast to the creamy, tart filling, adding a sophisticated touch that sets it apart.
Why This Key Lime Slab Pie Recipe Shines
Just look at it—isn’t it absolutely stunning? This pie was literally the bright, sunny spot in an otherwise cold and dreary January week. To add an extra touch of non-traditional charm and vibrant color, I adorned it with some fresh raspberries before serving. This not only enhances its visual appeal but also introduces a lovely hint of berry sweetness that complements the lime’s tang beautifully.
It’s interesting to note that many people mistakenly believe key lime pie should be green. However, true key lime pie, made with natural key limes, boasts a beautiful pale yellow hue. This is due to the natural color of the key lime fruit itself once it ripens. So, if you encounter a key lime pie with a vivid green color, it’s highly probable that food coloring has been added to achieve that vibrant shade. Our recipe celebrates the authentic, natural color and flavor of this beloved dessert.
The Intriguing Origin of Key Lime Pie
The widely accepted narrative places the origin of Key Lime Pie squarely in Key West, Florida. Local legend suggests it was created by “Aunt Sally,” the cook for Key West’s first millionaire, William Curry, using ingredients readily available on the island, primarily sweetened condensed milk (as fresh milk was scarce) and, of course, key limes. However, this delightful theory faced a strong challenge when the Borden Milk Company claimed to have invented the first Key Lime Pie in their New York City test kitchen in 1931. Their motive? To boost sales of their sweetened condensed milk, a key ingredient that doesn’t require refrigeration—perfect for the pre-refrigeration era and a clever marketing strategy.
Naturally, Floridians were, and still are, quite passionate about defending their claim as the true originators of this beloved citrus custard confection. The debate continues to this day, and depending on who you ask, the answer will likely vary. It’s a bit like the ongoing argument between Omaha and New York City over the invention of the Reuben sandwich. While New Yorkers often claim its birth at the Reuben’s Delicatessen, those of us in Omaha know the truth: the Reuben truly originated at the Blackstone Hotel in Omaha. But that, as they say, is a story for another recipe! For now, let’s just appreciate the deliciousness, regardless of its precise birthplace.
Understanding the Difference Between Key Limes and Regular Limes
While they both carry the “lime” name, Key Limes and standard Persian limes (the larger, deep green ones commonly found in supermarkets) possess distinct characteristics that profoundly impact their flavor profile and suitability for recipes. Key Limes are noticeably smaller, about the size of a golf ball, but don’t let their diminutive stature mislead you! They pack a far more aromatic and intense flavor than their Persian counterparts. Their thin, smooth skin transitions from a deep green when immature to a vibrant yellow when fully ripe, unlike Persian limes which remain green even when ripe.
Key Limes also tend to have more seeds and are renowned for containing more juice relative to their size. Their juice is more tart, yet also more fragrant and floral, with a unique bittersweet quality that is simply unparalleled for desserts like Key Lime Pie. Interestingly, Key Limes are more prevalent globally than they are in the U.S. commercial market, largely because many of the commercial crops in the Florida Keys were devastated by a hurricane in the 1920s and subsequently replaced with hardier Persian lime crops. Key Limes are also known by other names, such as West Indian limes or Mexican limes, reflecting their wider global presence.
Can You Substitute Regular Lime Juice for Key Lime Juice?
Frankly, yes, you *can* use regular Persian lime juice in a pinch. There’s no “Lime Police” that will confiscate your pie for daring to make a substitution! However, if you have the option, I strongly advise against it for optimal flavor. Key lime juice offers a unique balance of sweetness and acidity, coupled with a distinct aromatic quality that is difficult to replicate. Key limes are typically picked when they are still immature and green, but as they ripen, their skin turns yellow, and their acidity mellows, becoming sweeter and much more suitable for the delicate balance required in dessert recipes like Key Lime Pie.
If fresh key limes are absolutely unavailable and you must resort to a substitute, the best approach is to use a combination of half regular lime juice and half lemon juice. The lemon juice helps to mimic the brighter, slightly more complex tartness that key limes possess. Still, for that truly authentic, irresistible Key Lime Pie flavor, always reach for the key limes. You will undoubtedly be thankful you did, as the depth of flavor is simply incomparable.
Crafting the Perfect Flaky Pie Crust for Your Slab Pie
A truly exceptional Key Lime Slab Pie begins with an outstanding crust. For this flaky slab pie crust, you’ll need simple pantry staples: all-purpose flour, a touch of sugar for tenderness and slight sweetness, a pinch of salt to balance flavors, solid shortening for flakiness, an egg yolk for richness and binding, and a splash of cold milk to bring it all together. Using cold ingredients is key to achieving that desirable flaky texture, as it prevents the shortening from fully incorporating into the flour, creating pockets of steam during baking.
To begin, combine your shortening with the flour, sugar, and salt in a large mixing bowl. Using a pastry blender or your fingertips, cut the shortening into the dry ingredients until the mixture resembles coarse crumbs with some pea-sized pieces of shortening remaining. In a separate small bowl, whisk together the egg yolk and milk. Gradually add this wet mixture to the flour mixture, mixing gently with your hands until just combined. Be careful not to overmix, as this can develop the gluten too much, resulting in a tough crust.
Once the dough comes together, gently form it into a ball. Turn the dough out onto a lightly floured surface and roll it into a large rectangle, approximately 19×14 inches, to fit your sheet pan. Carefully transfer the rolled-out dough to your sheet pan, easing it into the corners and forming beautiful, decorative crust edges. Before baking, remember to prick holes generously into the bottom and sides of the crust with a fork; this prevents it from puffing up too much. Bake until it achieves a light golden brown, then remove and let it cool completely before adding the luscious filling.
The Silky, Zesty Key Lime Custard Filling
The heart of this Key Lime Slab Pie is its incredibly smooth and vibrant custard. The magic happens with just a few key ingredients: rich egg yolks for a silky texture and golden hue, sweetened condensed milk for that characteristic creamy sweetness and body, and, of course, fresh key lime juice and key lime zest for their unparalleled bright, tangy, and aromatic flavor. The zest is crucial here, as it contains the concentrated oils that provide the deep citrus notes. Using fresh ingredients makes all the difference in achieving that signature Key Lime Pie taste.
To prepare this exquisite key lime custard, begin by whisking the egg yolks together in a mixing bowl until they are smooth and slightly pale. Next, gradually add the sweetened condensed milk, the freshly squeezed key lime juice, and the fragrant key lime zest. Stir these ingredients together until they are thoroughly combined and the mixture is homogeneous. This simple combination creates a surprisingly thick and creamy custard that bakes beautifully. Once prepared, spread this delightful key lime filling evenly into your pre-baked and cooled pie crust. Bake it until the custard is just set, meaning it no longer jiggles excessively in the center. Allow it to cool slightly on the counter before transferring it to the refrigerator for at least 3 hours to chill completely, allowing the flavors to meld and the custard to firm up beautifully.
After the pie has thoroughly chilled and the custard is perfectly set, it’s time for the crowning glory: a generous layer of freshly whipped cream. In a clean mixing bowl, whip heavy whipping cream with some powdered sugar until stiff peaks form. The powdered sugar not only sweetens the cream but also helps stabilize it. Once whipped to perfection, spread this light and airy topping evenly over the cooled key lime slab pie, creating a beautiful contrast in both texture and color.
For an exquisite finish, garnish your Key Lime Slab Pie with additional lime zest, which adds another layer of aromatic citrus fragrance, and thin slices of key limes. These not only enhance the visual appeal but also offer a lovely burst of fresh flavor. The presentation is key to making this pie an unforgettable dessert, and these simple garnishes elevate it beautifully.
And for a delightful pop of color and complementary flavor, consider adding some fresh raspberries as well! The tartness of the raspberries pairs wonderfully with the key lime, and their vibrant red hue creates a stunning visual contrast against the pale yellow pie and white cream. This extra touch makes your slab pie even more special and appealing.
Serving and Storage Tips for Your Key Lime Slab Pie
Once fully chilled and garnished, your Key Lime Slab Pie is ready to be enjoyed! For the best flavor and texture, serve it directly from the refrigerator. The cold temperature ensures the custard remains firm and refreshing, and the whipped cream stays perfectly piped. To cut, use a sharp, clean knife for neat slices that showcase the distinct layers. This slab pie is excellent for serving a large group, as its shape allows for easy portioning into smaller squares or rectangles.
Leftovers (if there are any!) should be stored in an airtight container in the refrigerator. This pie holds up well for about 3-4 days, though the crust may soften slightly over time. For optimal freshness, you might consider adding the whipped cream topping only to the portions you plan to serve immediately, and then topping individual slices as needed. This helps keep the whipped cream looking its best and prevents it from weeping or dissolving into the custard over extended storage.
Love it? Pin it! Don’t Forget to Share This Recipe
If you’re as excited as I am about making this incredible Key Lime Slab Pie, you’ll want to ensure you can easily find this recipe again. Don’t let it get lost in the sea of online content! Before you navigate away, take a moment to pin this recipe to your favorite Pinterest recipe board. Sharing is caring, and your followers will surely thank you for introducing them to this sensational dessert!
For the Love of All Things Lime!
If you’re anything like me and have an insatiable love for all things lime, especially key lime, then you’re in for a treat! The bright, zesty, and refreshing flavor of lime is incredibly versatile, lending itself beautifully to everything from cocktails to main dishes and, of course, desserts. Beyond this amazing Key Lime Slab Pie, I have an array of other fantastic lime and key lime recipes that I know you’ll adore. Explore these favorites to satisfy all your citrus cravings:
- Key Lime Pie Smoothie (pictured above, a perfect breakfast or snack!)
- Cherry Limeade Baked Donuts (a sweet and tangy treat for breakfast or dessert)
- Cilantro Lime Rice (an essential side dish for Mexican-inspired meals)
- Key Lime Fizz Cocktail (a bubbly, zesty drink perfect for happy hour)
- Lime in the Coconut Bread (a tropical loaf cake that transports you to paradise)
- Cherry Limeade Sweet Rolls (a delightful twist on classic sweet rolls)
- Brazilian Lemonades (also known as Mini Vacation Cocktails, unbelievably refreshing!)
- Copy Cat Sonic Cherry Limeade Slush (recreate your drive-thru favorite at home)
- Key Lime Cupcakes (individual servings of key lime deliciousness)
- Key Lime & Grilled Pineapple Parfaits (a layered dessert with a smoky-sweet twist)
But for now, let’s keep dreaming of those sun-drenched Florida Keys and embrace the joy of creating this sensational, albeit non-traditional, Key Lime Slab Pie! It’s a dessert that truly brightens any day and is sure to become a beloved favorite in your home. Happy baking! 
LIKE THIS RECIPE?
Don’t forget to give it a ⭐️⭐️⭐️⭐️⭐️ star rating and
leave a comment below the recipe!
Print Recipe
Key Lime Slab Pie
Equipment
-
Wilton Performance Pans Aluminum Jelly Roll and Cookie Pan, 10.5 x 15.5-Inch
-
Citrus Zester
-
Manual Juicer Citrus / Lemon Squeezer
Ingredients
For the Crust
- 2 1/2 cups flour
- pinch of salt
- 1 Tablespoon sugar
- 1 cup shortening
- 1 egg yolk
- 1 cup milk
For the Key Lime Custard
- 8 egg yolks
- 2 14 ounce cans sweetened condensed milk
- 3/4 cup juice from fresh Key Limes
- 3 Tablespoons Key Lime Zest + more for garnishing
- 1 1/2 cups Whipping cream + 1/2 cup powdered sugar
- Sliced key limes and fresh raspberries for garnish if desired
Instructions
-
Preheat oven to 425 degrees.
-
To make the pie crust: In a bowl combine flour, sugar, salt and shortening with a pastry blender or your hands until it’s all incorporated. Add the egg yolk to a measuring cup, then add enough milk to make 2/3 cup. Whisk together. Pour the egg/milk mixture into the flour mixture and combine with your hands. The dough will be a little sticky. Form dough into a ball. Place dough ball on a floured surface and roll out into a rectangle measuring about 19×14″. Carefully fold the dough into sixths to make it easier to move onto a 15x10x1″ sheet pan. Trim crust at the pan’s edge and form a crust edge. Prick holes into the bottom and sides of the crust with a fork. Bake for 10-15 minutes, or until light golden brown. Remove and let cool.
-
Reduce oven to 325 degrees.
-
Prepare the custard: Whisk egg yolks in a mixing bowl. Add to them the condensed milk, lime juice and lime zest. Mix well, and spread into cooled pie crust. Bake for 20 minutes, until custard is set. Cool on the counter for about 30 minutes then place in the fridge for about 3 hours.
-
Whip cream and powdered sugar with your mixer, with a whisk attachment until stiff peaks form. Spread over the custard. Garnish with lime slices and zest, raspberries if desired.
-
Keep in the fridge.
Nutrition