Delia Smith Key Lime Pie Recipe

This classic Key lime pie is a wonderfully fresh and zesty dessert with a crisp biscuit base and a smooth, creamy filling. The balance of sharp lime and sweet condensed milk creates a beautifully light yet indulgent finish. It’s an easy recipe that feels impressive, making it perfect for both everyday treats and special occasions. From start to finish, it takes around 1 hour plus chilling time.

Ingredients

For the Biscuit Base

200g digestive biscuits, crushed
100g unsalted butter, melted

For the Filling

397g tin condensed milk
4 large egg yolks
100ml freshly squeezed lime juice (about 4–5 limes)
Finely grated zest of 2 limes

For the Topping

200ml double cream
1 tbsp icing sugar
Extra lime zest or slices, to decorate

How to Make Delia Smith Key Lime Pie

Prepare the oven: Preheat the oven to 180°C or 160°C fan. Place a shelf in the middle of the oven so the pie cooks evenly.
Make the base: Mix the crushed biscuits with the melted butter until evenly coated. Press the mixture firmly into the base and sides of a 20cm pie dish. Bake for 10 minutes, then set aside to cool slightly.
Mix the filling: In a bowl, whisk the egg yolks until slightly thickened. Add the condensed milk and whisk until smooth. Stir in the lime juice and zest until fully combined.
Bake the pie: Pour the filling into the prepared base and bake for 15 minutes, just until set but still with a slight wobble in the centre.
Cool and chill: Allow the pie to cool at room temperature, then transfer to the fridge and chill for at least 3 hours or until fully set.
Prepare the topping: Whip the double cream with icing sugar until soft peaks form.
Assemble and serve: Spread or pipe the whipped cream over the chilled pie and decorate with lime zest or slices before serving.

Tips for the Best Key Lime Pie

Why is my filling not setting properly?

Make sure the pie is baked long enough to just set in the centre and then chilled thoroughly for several hours.

Can I use bottled lime juice?

Fresh lime juice gives the best flavour, but bottled can be used in a pinch. Choose a good-quality one without added sugar.

How do I get a firm biscuit base?

Press the mixture very firmly into the tin and bake it briefly to help it hold together when sliced.

Can I make it ahead of time?

Yes, this pie is perfect for making a day in advance as it sets beautifully overnight.

Serving Suggestions

Serve chilled for the best texture
Add extra lime zest for a sharper finish
Pair with fresh berries for contrast
Enjoy with a cup of tea or coffee

Storage

Room Temperature

Not suitable for storing at room temperature for more than 2 hours due to the dairy content.

Refrigerator

Store covered in the fridge for up to 3 days. Keep it well covered to prevent it absorbing other flavours.

Freezing

Freeze without the cream topping for up to 1 month. Thaw overnight in the fridge and add fresh cream before serving.

Nutrition

Calories: 420 kcal
Carbohydrates: 38g
Protein: 7g
Fat: 27g
Saturated Fat: 16g
Sodium: 180mg

Nutritional values are approximate and may vary depending on ingredients used.

FAQs

Can I use regular limes instead of key limes?

Yes, regular limes work perfectly well and are easier to find. The flavour will still be fresh and tangy.

Do I need to bake the filling?

Yes, baking helps the filling set properly and gives it the classic texture of a key lime pie.

Can I make this pie without eggs?

Traditional key lime pie uses egg yolks, but you can try egg-free versions using alternative thickeners, though the texture will differ.

How do I know when the pie is done?

The centre should be just set with a slight wobble. It will firm up further as it cools and chills.