Smooth Condensed Milk Key Lime Pie

If you ask me, key lime pie is a little slice of Florida sunshine.

This classic dessert brings together the perfect balance of tart and sweet flavors in a buttery graham cracker crust. Fresh key lime juice gives it that signature zingy taste that makes your taste buds do a happy dance.

The filling is smooth and creamy, made with condensed milk that gets whipped up with those tiny key limes until it’s just right. A dollop of fresh whipped cream on top adds the finishing touch.

It’s a refreshing treat that feels right at home at summer barbecues or holiday gatherings – the kind of dessert that makes everyone smile.

What Kind of Limes Should I Use?

Key limes and Persian limes (the regular ones you typically find at the grocery store) can both work in this recipe, and you can even use a combination of the two. Key limes are smaller and have a more intense, slightly floral flavor compared to Persian limes, but they’re also more tedious to juice since you’ll need about 20-25 of them to get enough juice for this pie. Persian limes are larger and easier to work with – you’ll only need about 8-10 to get the same amount of juice. When zesting either type, just remember to avoid the white pith underneath the green skin, as it can make your pie taste bitter. If you can’t find fresh Key limes, bottled Key lime juice is a perfectly acceptable substitute.

Options for Substitutions

This Key Lime Pie recipe has some room for adjustments if you need them:

• Key limes: Regular Persian limes work perfectly fine here – they’re actually easier to juice! You’ll need about 6-8 Persian limes to get the same amount of juice as 20-25 key limes.
• Graham crackers/digestives: You can swap these with any plain cookie crumb – vanilla wafers, biscoff cookies, or even gingersnaps for a spicier crust.
• Pecans: Feel free to use graham crackers alone, or swap pecans with walnuts, macadamia nuts, or even coconut for a different twist on the crust.
• Sour cream: Full-fat Greek yogurt makes a good substitute – it adds the same tangy flavor and creamy texture.
• Heavy whipping cream: For the topping, this is best made with heavy cream, but you can use store-bought whipped topping in a pinch. Just skip the additional sugar and vanilla if you go this route.
• Sweetened condensed milk: This is a must-have ingredient that can’t be substituted – it’s what gives Key Lime Pie its signature texture and sweetness.

Watch Out for These Mistakes While Baking

The biggest challenge when making key lime pie is getting the perfect balance of tartness – using too much lime juice can make your pie unpleasantly sour, while too little will leave you with an overly sweet dessert that lacks the signature tang. A common mistake is zesting too deeply into the lime’s white pith, which adds unwanted bitterness to your pie – stick to the green outer layer only. For the crust, avoid over-processing the crackers and pecans into a fine powder, as this can lead to a dense, hard-to-cut base; instead, aim for a texture similar to coarse sand. When baking, keep a close eye on the filling – it should be just set with a slight jiggle in the center when you gently shake the pan, as overbaking can cause cracks and a rubbery texture. Finally, make sure your pie is completely cool before adding the whipped cream topping, and chill for at least 4 hours (preferably overnight) to allow the flavors to develop fully.

What to Serve With Key Lime Pie?

Key lime pie is a refreshing dessert that pairs wonderfully with a few simple accompaniments. A dollop of fresh whipped cream (besides what’s already on the pie!) is always welcome, and I like to add some fresh berries like raspberries or strawberries on the side for a pop of color and tartness. For a nice temperature contrast, try serving your pie with a scoop of vanilla ice cream – the cold, creamy vanilla is perfect against the tangy lime filling. If you’re serving coffee or tea with dessert, a cup of dark roast coffee or Earl Grey tea makes this citrusy treat even more enjoyable.

Storage Instructions

Keep Chilled: This key lime pie needs to stay cool and fresh in the fridge. Place it in an airtight container or cover it well with plastic wrap, and it’ll keep nicely for up to 4 days. The crust might soften slightly over time, but the filling will stay just as creamy and delicious!

Freeze: Want to make this ahead? You can freeze the pie without the whipped cream topping for up to 2 months. Wrap it tightly in plastic wrap, then in foil. When you’re ready to serve, thaw it overnight in the fridge and add fresh whipped cream topping just before serving.

Make Ahead: If you’re planning for a special occasion, you can make this pie a day or two in advance. Just hold off on the whipped cream topping until you’re ready to serve – fresh whipped cream is always best! The filling actually develops even more flavor after a day in the fridge.

Preparation Time	20-30 minutes
Cooking Time	25-35 minutes
Total Time	4-8 hours (including chilling time)
Level of Difficulty	Medium

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 3500-4000
• Protein: 40-50 g
• Fat: 250-280 g
• Carbohydrates: 350-400 g

Ingredients

For the crust:

• 5 tbsp unsalted butter (melted)
• 2 tbsp confectioners’ sugar
• 2 cups graham cracker crumbs (about 16 crackers)
• 1 cup pecans, toasted (finely chopped)

For the filling:

• 2 large egg yolks
• Pinch fine sea salt
• 1 tsp vanilla extract
• 1/3 cup sour cream (room temperature, makes it extra creamy)
• Zest from 10 key limes (avoid white pith, for best flavor and aroma)
• Two 14 oz cans sweetened condensed milk (I use Borden for smooth texture)
• 1 cup key lime juice (freshly squeezed preferred)

For the whipped cream topping:

• 2 tsp vanilla extract
• 2 cups heavy cream (cold, for best whipping)
• Pinch fine sea salt
• 1/4 cup powdered sugar

Step 1: Prepare the Graham Cracker-Pecan Crust

• 2 cups graham cracker crumbs
• 1 cup pecans, toasted
• 5 tbsp unsalted butter, melted
• 2 tbsp confectioners’ sugar

Preheat your oven to 350°F and line a 9-inch pie pan with parchment paper.

While the oven heats, pulse the graham cracker crumbs and toasted pecans in a food processor until they’re finely ground and resemble coarse sand.

Transfer to a bowl and stir in the melted butter and confectioners’ sugar until the mixture is completely moistened and holds together when pressed.

Press this mixture firmly and evenly into the prepared pan, creating an even layer on the bottom and up the sides.

Bake for 10 minutes until the crust is set and lightly golden, then remove and let cool while you prepare the filling.

Step 2: Prepare the Key Lime Filling Base

• Zest from 10 key limes
• 1 cup key lime juice
• 2 large egg yolks
• Two 14 oz cans sweetened condensed milk
• 1/3 cup sour cream
• 1 tsp vanilla extract
• Pinch fine sea salt

While the crust cools, zest 10 key limes using a microplane, being careful to avoid the white pith which can taste bitter.

Reserve the zest and juice the limes to yield 1 cup of fresh juice.

In a large bowl, whisk together the egg yolks, key lime zest, and vanilla extract until well combined.

Pour in both cans of sweetened condensed milk and the key lime juice, whisking until smooth and fully incorporated.

Gently fold in the room temperature sour cream until no streaks remain.

I like to add the sour cream last because it keeps the filling incredibly creamy and smooth—don’t skip this step!

Step 3: Bake the Pie

• filling mixture from Step 2
• prepared crust from Step 1

Pour the filling mixture from Step 2 into the cooled crust.

Bake at 350°F for 15-18 minutes until the filling is set around the edges but still has a slight jiggle in the center (about a 2-inch circle in the middle).

The filling will continue to set as it cools.

Remove from the oven and let cool to room temperature for about 30 minutes, then refrigerate for at least 4 hours or preferably overnight until fully chilled and set.

Step 4: Prepare the Whipped Cream Topping

• 2 cups heavy cream, cold
• 1/4 cup powdered sugar
• 2 tsp vanilla extract
• Pinch fine sea salt

About 30 minutes before serving, pour the cold heavy cream into a chilled bowl.

Using an electric mixer or whisk, whip the cream on medium-high speed until soft peaks form.

Add the powdered sugar, vanilla extract, and pinch of sea salt, then continue whipping until stiff peaks form.

I always chill my bowl and beaters before whipping heavy cream—this makes all the difference in getting a light, fluffy whipped cream that holds its shape.

Step 5: Finish and Serve

• chilled pie from Step 3
• whipped cream topping from Step 4

Remove the chilled pie from the refrigerator 10 minutes before serving to take the edge off the chill and let the flavors come forward.

Top each slice generously with the whipped cream from Step 4, or spread it over the entire pie if you prefer.

You can garnish with additional lime zest or thin lime slices for a beautiful presentation.