Key Lime Pie
If there’s one dessert that can carry summer from start to finish, it’s this. Tart, creamy key lime filling tucked into a buttery graham cracker crust—and topped with the softest whipped egg white topping that floats like a marshmallow cloud. It’s light, refreshing, and honestly… the kind of pie that disappears by the second slice.
This version skips the coconut or heavy cream and uses whipped egg whites for a topping that’s fluffy, delicate, and holds its shape beautifully. It’s fresh, simple, and perfect for any cookout, gathering, or weekend where you want something a little extra but not overdone.
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Recipe Tips
Use pasteurized egg whites for peace of mind—especially if serving guests who are pregnant, immunocompromised, or under 5.
Use a thermometer when making Swiss meringue—160°F is the sweet spot for food safety without overcooking.
Clean equipment matters—any grease or yolk in your mixing bowl will stop the egg whites from whipping properly.
Zest before juicing—and use a microplane for a clean, aromatic zest without the bitter pith.
Chill overnight if possible for the cleanest slices and best texture. The meringue will hold well and slice beautifully the next day.
Use a hot knife for clean cuts—just dip in hot water and wipe between slices.
Rewhip the meringue if needed—if it deflates slightly in the fridge, a quick whip brings it right back.
For a bakery finish, add lime zest on top of the toasted meringue before serving.
Ingredient Swaps:
No key limes ? Use regular limes or a combination of lemon and lime juice if key limes aren’t available. The flavor will still be bright, just a little less floral.
No powdered monkfruit sweetener ? Use regular powdered sugar in a 1:1 ratio. It gives a similar texture and holds up just as well in the egg white topping.
No cream of tartar ? Add ½ tsp lemon juice or white vinegar to stabilize the egg whites instead.
Gluten-free crust needed ? Use gluten-free graham crackers for the crust or try a crust made from crushed almonds or gluten-free shortbread.
Store-bought crust shortcut ? If you’re short on time, a store-bought graham cracker crust works just fine. Just make sure it’s the kind that’s bake-able.
Want a toasted finish? ? You can lightly torch the whipped topping or broil for 30–60 seconds, watching closely so it doesn’t burn.
Refrigerator: Store the finished pie in the fridge for up to 3 days. If you’ve already added the whipped topping, keep it loosely covered with plastic wrap or a domed container to avoid flattening the peaks.
Freezer: You can freeze the pie without the topping by wrapping it tightly in plastic wrap and foil. Freeze for up to 2 months. Thaw overnight in the fridge, then add the whipped egg white topping before serving.
Make-ahead tips: Bake the crust and filling a day ahead, then whip and top the pie right before serving for best texture and height.
more recipes to try:
Key Lime Pie
Ingredients
For the Graham Cracker Crust:
- 1 ½ cups graham cracker crumbs about 10–12 crackers
- 6 tbsp unsalted butter melted
- 2 tbsp sugar
- Pinch of sea salt
For the Key Lime Filling:
- 4 egg yolks
- Zest of 2 key limes or regular limes
- 14 oz sweetened condensed milk
- ½ cup key lime juice fresh or bottled, like Nellie & Joe’s
For the Swiss Meringue Topping:
- 4 egg whites pasteurized, room temperature
- ½ cup powdered monkfruit sweetener or powdered sugar
- ½ tsp cream of tartar
- 1 tsp vanilla extract optional
Instructions
- Preheat oven to 350°F (175°C). In a bowl, mix graham cracker crumbs, sugar, salt, and melted butter until the texture resembles wet sand. Press the mixture firmly into the bottom and sides of a 9-inch pie dish. Bake for 8–10 minutes until lightly golden. Let cool slightly.
- In a mixing bowl, whisk the egg yolks and lime zest for 1–2 minutes until pale and creamy. Add the sweetened condensed milk and whisk until smooth. Stir in the lime juice and let the mixture sit for 5 minutes to thicken slightly.
- Pour the filling into the baked crust. Bake at 350°F for 15 minutes until the edges are set and the center has just a slight wobble. Let the pie cool at room temperature for 30 minutes, then refrigerate for at least 4 hours or overnight.
- In a clean glass or metal bowl, whisk together the egg whites and powdered monkfruit sweetener (or sugar). Set the bowl over a saucepan of simmering water, making sure the bottom of the bowl doesn’t touch the water.
- Whisk constantly until the mixture reaches 160°F on a thermometer (this takes about 3–5 minutes). It should feel warm and the sugar should be mostly dissolved.
- Remove from heat. Add the cream of tartar and vanilla extract, then beat with an electric mixer on high speed for 5–8 minutes, until the meringue is thick, glossy, and holds stiff peaks.
- Once the pie is fully chilled, top with the Swiss meringue. Spoon, swoop, or pipe as desired. For a classic finish, lightly toast the peaks with a kitchen torch just before serving.
