My very first encounter with a key lime pie was 16 years ago. At that time, my husband and I would chill at our favourite tea house after our Saturday lunch. He’d typically order a slice of key lime pie with a pot of jasmine tea. While I would vary the pleasures by ordering a different dessert, I couldn’t resist to steal a bite from his plate. So naturally, a key lime pie came to my mind when I saw that can of sweetened condensed milk in the pantry and the excessive amount of limes in the fridge. I like the sweetness and acidity. For that reason, I can eat a whole pie just by myself. As it’s quite a rich dessert, you can understand why I don’t bake it often.

What you will need to make my key lime pie recipe
Biscoff biscuits – I absolute love this biscuit for its taste and its crunch. It is also my choice of biscuit when I want to bake a cheesecake. You can of course use graham crackers or digestive biscuits instead
Butter – it plays the role of binder here
Sweetened condensed milk – I personally find it sweet enough so I don’t add any sugar to the lime mixture
Cream cheese – make sure to take it out of the fridge before so it is at room temperature and easier to incorporate without any lumps
Egg yolk – for a firmer and creamier pie
Lime juice – a key lime pie is made with limes. I use Persian limes that are commonly sold at the supermarkets. They are bigger and have a mild flavour. You will need around 10 limes. You can substitute with lemon juice, but it’s then called lemon pie.
Lime zest – preferably use organic limes as the zest adds so much more flavour
Whipping cream – it is also called double cream or liquid full cream, depending on where you live. It has to contain minimum 35% full fat or it won’t work! Chill the cream in the freezer for at least 15 minutes as well as the mixing bowl
Mascarpone cheese – use room temperature mascarpone to easily incorporate into the cream
3 steps to make key lime pie
Step 1 – make the biscoff pie crust
First and foremost, preheat the oven at 350F with the rack at the middle
The easiest and fastest way for me is to blend the biscuits in a food processor. We get an even result effortlessly. You can of course place the biscuits in a freezer bag and bash them with a rolling pin. As you know I try to avoid generating any unnecessary waste whenever I can. So, my second option would be using a mortar and pestle.
Then transfer the crumbs into a mixing bowl and pour the melted butter onto it. Combine well and firmly press the mixture into the pie pan base (I either use my 9×9 inches square pan or 10 inches circle pan). I recommend you use something with right angles to evenly flatten the crust and help push the crumbs to the sides. Then set the crust in the fridge while preparing the filling.

Step 2 – prepare the key lime pie filling
First, grate the zest of two limes using a zester. Then squeeze the lime juice into a measuring cup. I took a ceviche class few years ago. I learned it’s best not to use a citrus juice squeezer as the pressure will release the bitterness of the limes. I confirm this is also true for key lime pie. It’s best to cut the limes in three around the central core to manually express the most juice. Eventually fish out the seeds and set aside.

Combine the cream cheese with the sweetened condensed milk in a mixing bowl. Then add the egg yolks. Once well incorporated, pour the lime juice and zest into the mixture. Whisk well. Pour the filling into the pie crust and bake for about 15 minutes. Remove the key lime pie from the oven and let it cool completely. Then place the pie in the fridge for about an hour before topping it with the whipped cream.

Step 3 – make the whipped cream
Adding mascarpone helps to stabilize the whipped cream that will hold. I use a spatula to soften the mascarpone by spreading it into the mixing bowl. Once it has loosened up, I add half of the whipping cream. Using the electric hand whisk, I slowly combine the softened mascarpone with the cream on medium low speed until there is no lumps left. Then I add the remaining cream and beat at a higher speed until medium to stiff peaks. Finally, place the whipped cream in the fridge before spreading it all over the completely cooled key lime pie.

Note that I don’t add any sugar here. The crust and filling are sweet enough. I personally like the contrast of the unsweetened whipped cream with the rest.
How long does the key lime pie last?
I recommend you keep it in the fridge for no more than 2 days due to the home-made whipped cream. I usually slice them into small squares and store in food containers. We would enjoy one on the go whenever we feel having one. Love biting at these when they qre just out of the fridge, so refreshing!
Do you know what main course would pair super well with my key lime pie? My salmon poke bowl! This is a super combination for the summer, trust me! If you try my recipe, don’t forget to tag me on Instagram
My easy key lime pie recipe
Course: DessertCuisine: AmericanDifficulty: Easy8
servings30
minutes15
minutesA super easy and flavourful key lime pie made with a biscoff pie crust
Ingredients
- For the pie crust
200 g biscoff biscuits
50 g butter
- For the pie filling
1 can of sweetened condensed milk
200 g cream cheese
2 egg yolks
120 ml lime juice – around 10 Persian limes
The zest of two limes
- For the whipped cream
200 g whipping cream
2 tbsp mascarpone cheese
Directions
- Preheat the oven at 350F with the rack at the middle
- Prepare the crust
- Melt the butter in a small saucepan at low heat
- Using a food processor grind the biscoff biscuits to powder and transfer to a mixing bowl
- Stir in the melted butter and combine well
- Line the pie pan with a parchment paper and press the crumbs firmly down the pan and up the sides
- Place the pie pan in the fridge
- Make the filling
- Squeeze the lime juice
- In another mixing bowl combine the cream cheese with the sweetened condensed milk
- Add in the eggs and whisk well
- Pour the lime juice and add the zest
- Combine well and pour onto the pie crust
- Bake for about 15 minutes
- Whip the cream
- Soften the mascarpone with a spatula onto the mixing bowl wall
- Add half of the whipping cream and whisk at medium speed until no lumps left
- Add the rest of the cream and whisk at higher speed until medium to stiff peaks
- Store the whipped cream in the fridge until ready to top the pie with and serve
Notes
- You can garnish the key lime pie with additional lime zest or thin lime slices