Classic Key Lime Pie Recipe (Easy)

Tart, creamy, and impossibly refreshing, key lime pie is Florida’s gift to dessert lovers. A buttery graham cracker crust holds a silky filling made from just four ingredients: key lime juice, sweetened condensed milk, egg yolks, and zest. Baked just until set and served ice cold with whipped cream, it is the perfect balance of sweet and puckery.

True key limes are smaller, seedier, and more aromatic than common Persian limes, with a distinctive floral tartness. If you cannot find fresh key limes, bottled key lime juice is an excellent substitute and far better than regular lime juice for authentic flavor.

Why This Key Lime Pie Recipe Works

The filling is a chemical magic trick: the acid in the lime juice reacts with the proteins in the condensed milk and egg yolks, thickening the mixture even before it hits the oven. This means the pie needs only a brief bake to set fully, giving it an ultra-smooth, creamy texture without any eggy taste. Using sweetened condensed milk (not evaporated) provides both sweetness and the proteins needed for the reaction.

Chilling the pie thoroughly is essential. The filling continues to firm as it cools, and key lime pie must be served cold for the full refreshing effect.

Ingredients for Key Lime Pie

For the graham crust:

• 1 1/2 cups (180g) graham cracker crumbs
• 1/4 cup (50g) granulated sugar
• 6 tablespoons (85g) unsalted butter, melted
• Pinch of fine salt

For the filling:

• 1 can (14 oz) sweetened condensed milk
• 4 large egg yolks, at room temperature
• 3/4 cup (180ml) key lime juice (fresh or bottled)
• 2 teaspoons key lime zest
• Pinch of fine salt

For the topping:

• 1 1/2 cups (360ml) heavy whipping cream, cold
• 3 tablespoons powdered sugar
• 1 teaspoon pure vanilla extract
• Lime slices and extra zest, for garnish

Juicing key limes: You will need about 12 to 15 key limes for 3/4 cup of juice. Roll them firmly on the counter before cutting to maximize juice. Bottled key lime juice (such as Nellie & Joe’s) is a worthy shortcut.

How to Make Key Lime Pie

1. Prep. Preheat the oven to 350°F (175°C).
2. Make the crust. Stir the crumbs, sugar, melted butter, and salt until evenly moistened. Press very firmly into a 9-inch pie plate, going up the sides. Bake 10 minutes until lightly golden. Cool slightly.
3. Mix the filling. Whisk the condensed milk, egg yolks, lime juice, zest, and salt until completely smooth. Let sit 5 minutes; it will thicken slightly from the acid reaction.
4. Bake. Pour into the crust and bake 15 to 18 minutes, until the edges are set but the center still jiggles slightly. Do not overbake; the pie sets as it cools.
5. Chill. Cool to room temperature, then refrigerate at least 4 hours or overnight. The pie must be thoroughly cold.
6. Top and serve. Beat the cold cream, powdered sugar, and vanilla to firm peaks. Spread or pipe over the chilled pie. Garnish with lime slices and zest. Serve ice cold.

Tips for the Best Key Lime Pie

Do not overbake. The filling should jiggle like gelatin, not slosh. Overbaking makes it rubbery and dulls the bright lime flavor.

Chill, chill, chill. This pie is at its best after an overnight rest. The flavors meld and the texture becomes perfectly creamy.

Zest matters. The zest carries the floral key lime aroma that juice alone cannot provide. Do not skip it.

Variations

Make key lime bars in a 9×13-inch pan (same crust, double the filling, bake 20 to 25 minutes). Add a layer of raspberry puree under the filling for raspberry-key lime pie. For coconut-key lime pie, add 1/2 cup of toasted coconut to the crust and coconut extract to the whipped cream.

Storage

Refrigerated, the pie keeps for 4 days. The whipped cream is best fresh, so top just before serving if making ahead. Freeze the untopped pie for 3 months; thaw in the refrigerator and add fresh whipped cream.

This key lime pie is pure sunshine: tart, creamy, and utterly refreshing. One slice and you will understand why it is a legend.

Key Lime Pie FAQs

Can I use bottled key lime juice?
Yes, and it is excellent. Bottled key lime juice is made from real key limes and gives authentic flavor. It is far better than substituting regular lime juice, which lacks the distinctive floral notes.

Should key lime pie be green?
No. Authentic key lime pie is pale yellow from the egg yolks and condensed milk. Bright green pies use food coloring. Do not add coloring; the natural pale gold color is the mark of the real thing.

How jiggly should the center be when done?
Like set gelatin: the edges firm, the center with a slight wobble. It sets fully as it chills. Overbaking dulls the bright lime flavor and makes the texture rubbery.

Can I freeze key lime pie?
Yes, the untopped pie freezes well for up to 3 months. Thaw in the refrigerator and add fresh whipped cream before serving. The texture remains creamy and smooth.