Quick Recipe Version (TL;DR)
Quick Ingredients
- 1 1/2 cups (150 g) graham cracker crumbs
- 1/3 cup (65 g) granulated sugar
- Pinch fine sea salt
- 6 tbsp (85 g) unsalted butter, melted
- 4 large egg yolks (room temperature)
- 1 can (14 oz/396 g) sweetened condensed milk
- 2/3 cup (160 ml) fresh key lime juice, strained
- 1/4 cup (60 g) sour cream
- 2 tsp finely grated lime zest
- 1 cup (240 ml) cold heavy cream
- 2 tbsp (15 g) powdered sugar
- 1/2 tsp vanilla extract
- Extra lime zest and thin lime slices, for garnish
Do This
- 1. Heat oven to 350°F (177°C). Zest and juice limes; strain the juice.
- 2. Mix crumbs, sugar, salt, and melted butter; press into a 9-inch pie dish. Par-bake 8 minutes; cool 10 minutes.
- 3. Whisk yolks and condensed milk until thick and glossy. Whisk in sour cream, zest, and juice until smooth.
- 4. Pour filling into crust; bake 12–15 minutes until edges are set and center jiggles slightly.
- 5. Cool on a rack 20 minutes, then chill 3–4 hours until cold and set.
- 6. Whip cream, powdered sugar, and vanilla to medium peaks.
- 7. Swirl whipped cream over pie; garnish with lime zest. Slice and serve.
Why You’ll Love This Recipe
- Bright, authentic key lime flavor from real juice and zest.
- Ultra-creamy filling that sets perfectly without cracks.
- Buttery, crisp graham cracker crust that cuts cleanly.
- A cool, lightly sweet whipped cream crown that balances the tang.
Grocery List
- Produce: Key limes (or regular limes), extra limes for garnish
- Dairy: Unsalted butter, sour cream, heavy whipping cream
- Pantry: Graham crackers, granulated sugar, powdered sugar, sweetened condensed milk, vanilla extract, fine sea salt
Full Ingredients
Graham Cracker Crust
- 1 1/2 cups (150 g) graham cracker crumbs (about 10 full cracker sheets)
- 1/3 cup (65 g) granulated sugar
- Pinch fine sea salt
- 6 tbsp (85 g) unsalted butter, melted
Creamy Key Lime Filling
- 4 large egg yolks, at room temperature
- 1 can (14 oz/396 g) sweetened condensed milk
- 2/3 cup (160 ml) fresh key lime juice, strained (or regular lime juice for a great substitute)
- 1/4 cup (60 g) sour cream
- 2 tsp finely grated lime zest (from 4–6 key limes or 1–2 regular limes)
Whipped Cream Crown
- 1 cup (240 ml) heavy whipping cream, very cold
- 2 tbsp (15 g) powdered sugar
- 1/2 tsp vanilla extract
- Pinch fine sea salt
Garnish (optional)
- Extra finely grated lime zest
- Very thin lime wheels or wedges
Step-by-Step Instructions
Step 1: Prep, preheat, and pan
Position a rack in the center of the oven and heat to 350°F (177°C). Lightly butter a 9-inch standard pie dish (not deep-dish). Zest the limes before juicing, then strain the juice to remove pulp and seeds; set both aside.
Step 2: Make and press the crust
In a bowl, stir together graham cracker crumbs, granulated sugar, and a pinch of salt. Drizzle in melted butter and mix until the crumbs look uniformly damp and hold together when pinched. Pour crumbs into the pie dish and press them firmly across the bottom and up the sides using the bottom of a measuring cup. Aim for even thickness with no bare spots.
Step 3: Par-bake the crust
Bake the crust for 8 minutes until fragrant and just set. Transfer to a rack and cool for 10 minutes. This step keeps the crust crisp under the creamy filling.
Step 4: Whisk the filling until glossy
In a medium bowl, whisk egg yolks and sweetened condensed milk for 1–2 minutes until slightly thickened and glossy. Whisk in sour cream and lime zest until smooth. Finally, whisk in the lime juice until fully combined. The mixture will loosen, then slightly thicken as it sits—this is perfect.
Step 5: Bake until just set
Pour the filling into the warm crust. Bake 12–15 minutes, until the edges are set and the center has a gentle wobble when you nudge the pan. Do not overbake; the pie will finish setting as it cools.
Step 6: Cool, then chill
Cool the pie on a rack for 20 minutes, then refrigerate uncovered until cold and set, at least 3 hours (4 hours yields the cleanest slices). Once cold, you can loosely cover the pie.
Step 7: Whip the cream
In a chilled bowl, whip the heavy cream, powdered sugar, vanilla, and a small pinch of salt to medium peaks—softly billowy with structure, not stiff. Medium peaks spread beautifully and stay silky.
Step 8: Crown, garnish, and serve
Swirl the whipped cream over the chilled pie or pipe decorative rosettes. Finish with a shower of lime zest and a few delicate lime wheels. Slice with a warm, dry knife for clean cuts, wiping between slices. Serve cold.
Pro Tips
- Zest first, juice second. Cold limes are easier to zest; room-temp limes yield more juice. Roll limes on the counter to release more juice.
- Do not overbake. Pull the pie when the center still jiggles slightly; overbaking can cause a rubbery texture.
- For a sturdy crust, press firmly and evenly. If crumbs stick to your cup, line it with parchment.
- Use fresh lime juice for the brightest flavor; bottled juice can taste dull. Regular limes work if key limes are unavailable—add an extra 1/2 teaspoon zest.
- Ultra-clean slices: Chill at least 4 hours and warm your knife under hot water, then dry before each cut.
Variations
- Gingersnap crust: Swap graham crumbs for gingersnap crumbs for a warmly spiced contrast.
- Toasted coconut crown: Fold 1/2 cup toasted coconut into the whipped cream and sprinkle more on top.
- Mini tartlets: Press crust into a 12-well muffin tin with liners; bake crusts 5 minutes, fill, and bake 8–10 minutes.
Storage & Make-Ahead
Pie keeps, covered and refrigerated, for up to 3 days. For best texture, add the whipped cream within 4 hours of serving. The un-topped pie can be frozen (well-wrapped) for up to 2 months; thaw overnight in the refrigerator and crown with fresh whipped cream before serving. Whipped cream can be made a few hours ahead; re-whisk briefly if needed.
Nutrition (per serving)
Approx. 520 calories; 34 g fat; 51 g carbohydrates; 7 g protein; 39 g sugars; 250 mg sodium. Estimates only, based on 8 servings.
