This Key Lime Pie is the dessert I wheel out every time someone says "bring something sweet" and I want zero effort for maximum compliments.
It's got the same tangy citrus hit as my Coconut & Lime Slice and my Classic Homemade Lemon Tart, but with a buttery biscuit base and a cloud of whipped cream on top.
A Quick Look At The Recipe
✅ Recipe Name: Key Lime Pie
🕒 Ready In: 10 minutes prep + 25 minutes baking + at least 4 hours chilling
👪 Serves: 16 slices
🍚 Calories: 218kcal per slice
🥣 Main Ingredients: plain sweet biscuits, butter, sweetened condensed milk, lime juice, eggs, cream
📖 Dietary Info: freezer-friendly (minus the cream topping), easily halved for a smaller tin
⭐ Why You'll Love It: just 10 minutes of hands-on prep for a dessert that tastes like a tropical holiday.
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I have made this three times over the past week, one which I took to dinner with friends, one for a family gathering and another which is in the freezer awaiting the next social event. So easy to make and demolished by all.
- Katy
If you're all about citrus desserts like I am, my No-Bake Lemon Cheesecake, Creamy Lemon Crumble Bars and Lemon Meringue Pie get just as much love in my house.
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Why You're Going To Love This Recipe
- Only 10 minutes of hands-on work. Crush, mix, press, pour, and the oven does the rest.
- Tastes like a slice of the tropics even in the middle of a Melbourne winter, which is honestly when I make it most.
- Freezer-friendly (minus the cream topping), so there's always a slice tucked away for later.
- No fancy equipment needed. Just a bowl, electric beaters and a loose-bottomed tin.
Pie Ingredients
Three simple layers, a biscuit base, a tangy filling and a whipped cream topping. Nothing fancy, but a few of these are worth getting right.
Note: Scroll to the recipe card at the bottom for the ingredient quantities and full detailed method.
- The biscuit base - Arnott's Granita or Marie biscuits work perfectly, or graham crackers if you're overseas. I've also used ginger nut biscuits when I wanted something with a bit more spice, and it worked a treat.
- Sweetened condensed milk needs to be full-fat, not the light or skim version. This isn't really about flavour, it's chemistry. The acid in the lime juice reacts with the milk proteins to thicken the filling, and a lighter version just doesn't have enough fat and protein to set properly.
- Lime juice - genuine key limes basically don't exist on Australian supermarket shelves, so don't waste your Saturday morning hunting for them. Ordinary limes from Coles or Woolies give you almost exactly the same tang.
- Four whole eggs go into this filling, rather than just yolks like some American versions use. It gives a firmer, more custard-like set, which I actually prefer because it slices so much more cleanly.
- Use pouring or thickened cream for the topping, not "light" cream. Light cream won't whip no matter how long you beat it, trust me, I've stood there with the beaters going way too long finding that out the hard way.
Variations
- Add crunch to the base: swap half the biscuits for macadamia nuts blitzed through the food processor. It's not traditional, but it's ridiculously good.
- Swap in ginger nut biscuits for the crust if you want something warmer and spicier. My mum's been doing this for years and swears by it.
- Want it extra creamy? Add a couple of tablespoons of sour cream to the filling before baking. It softens the tang without dulling the lime flavour.
- Turn it into individual serves for a party by dividing the mixture between mini tart tins instead of one big pie, and cut the baking time down to about 10 minutes. Great for footy finals when everyone wants their own slice.
How To Make Key Lime Pie
Four easy steps, and about 10 minutes of actual hands-on work.
Note: Scroll to the recipe card at the bottom for the ingredient quantities and full detailed method.
- Step 1: Make the crumb base. Preheat the oven to 160°C fan-forced and grease a 22cm loose-bottomed tin. Crush the biscuits to fine crumbs, mix through the melted butter, then press firmly into the base and sides of the tin.
- Step 2: Bake the base. Bake for 10 minutes, then set aside to cool completely. This keeps the base crisp once the wet filling goes in on top.
- Step 3: Make the filling. Beat the condensed milk, lime juice, eggs and zest with electric beaters until thick and creamy, about 4-5 minutes, then pour gently into the cooled base.
- Step 4: Bake, chill and top. Bake for 15 minutes or until just set, then chill in the fridge for at least 4 hours (overnight's even better). Whip the cream, spread over the top and finish with a scattering of lime zest.
Recipe Tips
- Don't rush the chilling time. It needs a full 4 hours in the fridge, overnight is even better, or you'll be serving lime soup instead of pie.
- The filling won't rise as it bakes, so you can pour it in almost right to the top of the crust.
- If the crumb mixture is too crumbly to press into the tin, add another tablespoon or two of melted butter and mix again.
- One time I forgot to bake the base first and went straight to the filling. It never crisped up properly and went soggy underneath by day two, so don't skip that first 10 minute bake, it genuinely matters.
- Storage: keep in an airtight container in the fridge for up to 3 days.
- Freezing: freeze the pie without the cream topping, wrapped tightly in plastic wrap and then foil, for up to 3 months. Defrost overnight in the fridge, then add the cream and lime zest just before serving.
Key Lime Pie FAQs
Yes, and most people do. Genuine key limes are hard to find outside the US, and in Australia you basically won't see them at Coles or Woolies at all. Ordinary limes give a slightly less floral flavour, but you honestly won't notice the difference once the condensed milk and biscuit base are in the mix.
Yes, it's actually better made ahead. The flavours settle overnight in the fridge and it slices far more cleanly once fully chilled. Just hold off on the cream topping until you're ready to serve.
This almost always comes down to the condensed milk. Skim, light or condensed coconut milk don't have enough fat and protein for the lime juice's acidity to thicken the mixture the way it should. Stick with a full-fat tin and check your base isn't still warm when you pour the filling in.
Cold, always. It needs several hours in the fridge to firm up enough to slice cleanly, so this isn't a dessert you can rush straight from oven to table.
Yes, but leave the cream topping off until serving day. Wrap the baked, cooled pie tightly in plastic wrap and then foil, and freeze for up to 3 months. Defrost overnight in the fridge, then whip your cream and add it fresh before slicing.
More Pie Recipes You'll Love
If pie is your love language too, here's a few more worth adding to the rotation:
Key Lime Pie
Ingredients
- 250 g plain sweet biscuits like Arnott's Granita, Marie or Graham Crackers
- 125 g butter melted
- 395 g sweetened condensed milk full fat (not skim)
- ½ cup lime juice
- 4 eggs large, room temperature
- 1 teaspoon lime zest grated
- 300 ml whipping or thickened cream for topping
- 1 tbs lime zest for grating
Instructions
Conventional Method
- Preheat oven to 160 degrees celsius (fan-forced).
- Grease a 22cm loose-bottomed tin and set aside.
- Crush the biscuits until they resemble fine crumbs. Add the melted butter and mix to combine.
- Press the biscuit mixture firmly into the base and sides of the tin. Bake for 10 minutes in the oven. Remove and allow to cool.
- Using electric beaters or a stand mixer, beat the sweetened condensed milk, lime juice, eggs and lime zest until thick and creamy (approximately 4-5 minutes).
- Gently pour the liquid into the prepared base and bake for 15 minutes or until set. Allow to cool in the fridge for a minimum of 4 hours (preferably overnight).
- Serve with whipped cream and extra grated lime zest.
Thermomix Method
- Preheat oven to 160 degrees celsius (fan-forced). Grease a 22cm loose-bottomed tin and set aside.
- Melt the butter in the Thermomix for 3 minutes, 80 degrees, Speed 2 (or until melted). Add the biscuits and crush for 5 seconds, Speed 8. Scrape down the sides of the bowl and repeat for a further 5 seconds.
- Firmly press the mixture into the base and sides of the prepared tin and bake for 10 minutes. Remove from oven and allow to cool.
- Place the sweetened condensed milk, lime juice, eggs and lime zest into a clean and dry Thermomix bowl and mix for 45 seconds, Speed 4. Scrape down the sides and mix for a further 45 seconds or until thick and creamy.
- Gently pour the liquid into the prepared base and bake for 15 minutes or until set.
- Allow to cool in the fridge for a minimum of 4 hours (preferably overnight). Serve with whipped cream and extra grated lime zest.
Jo Watson says
Hi There , mine has been cooking for 30 minutes still not quite firm in the centre .I used a loose bottom cheesecake pan instead of a pie dish .I'm assuming this is whats extending the cooking time. Well I Hope ?
Lucy says
Hi Jo, a loose bottom cheesecake pan would be fine to use. All ovens are different so yours may just need a little longer to cook!
Anney says
Absolutely foolproof!! Fanastic texture! Baking the crust for 10 minutes really is a super idea. I put my bikkies in a blender & " mulched" them to the consistency of " fine sand", exactly 250gm to 125gm of melted butter & it was a perfect ratio. I used the 'new' flavored salted caramel tart Scotch finger biscuits. My limes from the tree at home were quite tart & not as juicy as usual & the pulp was getting into the juice. But as the recipe said to add zest to the main wet mix, I thought, "what oh"& decided not to get finicky in straining the juice & put it all in. I'm talking of juice vessicles & not any nasty pith, mind you. Well like I said,texture of pie is brilliant, can't feel any of the pulp that I put in and that tangy bit of zest just suits the sweetness of the pie & in making this again I definitely would leave it in.
Lucy says
Hahahaha! I love this!!! So glad you enjoyed it!
Em says
Hiya! My filling never ended up becoming thick and creamy. I used condensed coconut milk. Would that have made a difference? Also, I noticed a lot of other recipes called for egg yolk. Could that have been the problem?
Thanks!
Lucy says
Hi Em, the reason it didn't thicken is because you need to use sweetened condensed milk not condensed coconut milk. The lime juice and the dairy in sweetened condensed milk combine to curdle and thicken. This doesn't happen with coconut milk as it doesn't contain any dairy.
Katy says
I have made this three times over the past week, one which I took to dinner with friends, one for a family gathering and another which is in the freezer awaiting the next social event.
So easy to make and demolished by all.
Lucy says
That is wonderful to hear!