6-Inch Key Lime Pie

Easy Small-Batch Recipe for Date Nights and Small Gatherings

Bright, creamy, and packed with citrus flavor, this 6-inch Key Lime Pie is the perfect small-batch dessert when you don't need a full-size pie. Made with Nellie & Joe's Key West Lime Juice, sweetened condensed milk, egg yolks, and a small amount of white chocolate, the filling is bright and tart with just enough richness to round out the sharp citrus flavor.

My favorite version starts with a Biscoff cookie crust. The caramelized cookie flavor pairs beautifully with the bright lime filling and gives this little pie a lot more personality than the traditional graham cracker crust.

At just 6 inches, it's my "Date Night" size, perfect for two generous servings or four smaller slices.

Simple ingredients. Big lime flavor.

Feeding a crowd? Make my full-size 9-Inch Key Lime Pie instead.

Cookie Crust Options

Each of these works well, but they create very different pies.

Good: Graham Crackers
The classic choice. Mild, buttery, and familiar, with just enough sweetness to let the lime filling shine.

Better: Lorna Doone Shortbread Cookies
A richer, buttery crust with a more delicate crumb that pairs beautifully with the creamy filling.

Best: Biscoff Cookies ⭐
My favorite. The caramelized spice of Biscoff cookies adds incredible depth without overpowering the bright citrus flavor.

It's the crust I use whenever I want to make an already great Key Lime Pie even better.

See my Cookie Crust Recipes

Yield: One 6-inch pie
Servings: 2–4
Prep Time: 15 minutes
Bake Time: 12–15 minutes
Chill Time: At least 4 hours

Ingredients

Biscoff Cookie Crust

90g Biscoff cookies, finely crushed (about 12 cookies)
35g unsalted butter, melted (2½ tablespoons)
Pinch of kosher salt, optional but recommended

Key Lime Filling

220g sweetened condensed milk
2 large egg yolks, room temperature
65g Nellie & Joe's Key West Lime Juice
Zest of ½ lime, optional
22g mini white chocolate chips

Instructions

1. Prepare the Biscoff Crust

Preheat the oven to 350°F (175°C).
Finely crush the Biscoff cookies and combine with the melted butter and a small pinch of kosher salt.
Press the mixture firmly and evenly across the bottom and up the sides of a 6-inch pie pan.
Bake for 8 minutes, then remove from the oven and allow the crust to cool slightly while you prepare the filling.

2. Make the Key Lime Filling

In a medium bowl, gently whisk the sweetened condensed milk and egg yolks until smooth.
Add the Key lime juice and lime zest and whisk gently just until completely combined.
Stir in the mini white chocolate chips.

Man-Made Tip: Keep the whisking gentle. Unlike a cake batter, there's no benefit to incorporating air into Key Lime Pie filling. Gentle mixing gives you a smoother, creamier filling and helps prevent bubbles from forming across the surface while it bakes.

3. Fill the Pie

Pour the filling into the prepared Biscoff crust.
Gently tap the pie pan against the counter a few times to encourage any trapped air bubbles to rise to the surface. Pop any remaining large bubbles with a toothpick.

4. Bake

Bake at 350°F (175°C) for 12–15 minutes.
The pie is done when the edges are set but the center still has a slight jiggle when the pan is gently moved. The filling should not puff, brown, or crack.
Don't wait for the center to become completely firm. The filling will continue to set as it cools and chills.

5. Cool and Chill

Allow the pie to cool completely at room temperature.
Refrigerate for at least 4 hours before serving. For the best texture, chill overnight.

Frequently Asked Questions

What Kind of Lime Juice Should I Use?

For Key Lime Pie, use Key lime juice, not juice from regular limes. Key limes are smaller and have a distinctive tart, aromatic flavor that gives the pie its characteristic taste.
You can certainly squeeze fresh Key limes, but they're tiny, full of seeds, and you'll need quite a few to get enough juice. I've done it, and for this pie I don't think the extra work is necessary.
I use Nellie & Joe's Key West Lime Juice. It gives me consistent Key lime flavor, it's easy to measure, and you can find it at most grocery stores, usually near the bottled lime juice or cocktail mixers.

Why Biscoff?

Graham crackers are the traditional choice for Key Lime Pie, and they'll certainly work here. But Biscoff is my favorite.
The caramelized cookie flavor adds a deeper, almost toasted note that balances the tart lime without competing with it. For this 6-inch version, 90g of Biscoff cookies and 34g of butter gives you enough crust to cover the bottom and sides without overwhelming the filling.

Why Add White Chocolate?

White chocolate isn't traditional in Key Lime Pie, but it's one of my favorite additions.
A small amount of mini white chocolate chips adds richness without taking away from the bright lime flavor. The cocoa butter and milk solids help round out the sharp citrus acidity, while the little pockets of white chocolate add a creamy contrast to the tart filling.
It doesn't technically make the pie less sweet, but I find that it makes the sweetness taste more balanced. The added richness gives the filling another layer of flavor instead of leaving you with just the sweetness of condensed milk competing against tart lime.
The key is not to overdo it. 22g is plenty for this 6-inch pie. You should notice the added richness, but the Key lime should still be the star.