These delicious Key Lime Bars feature a buttery and crumbly shortbread crust, topped with a creamy and zesty key lime filling for a great way to serve a bunch of people with a twist on this classic pie.
Table of Contents
This Key Lime Bars recipe results in a caramelized top and creamy center offset by the crushed biscuit base. Do you enjoy lime desserts? Let me know your favorite in the comments below!
Ingredients and substitutions for Key Lime Bars
- Graham crackers or digestive biscuits: These will need to be finely crushed for the base.
- Butter: It needs to be melted and I prefer using unsalted, especially with those crackers adding salt, but salted won't make too much difference here.
- Sweetened condensed milk: This creates a sweetness alongside the lime juice and is an essential to any key lime dessert.
- Egg yolks: The egg yolks alongside the condensed milk creates a custard texture to this filling.
- Lime juice: The very core of this recipe is the lime juice which adds a bright and zesty flavor to the custard filling.
- Heavy cream: The heavy cream balances out the sweetness in the condensed milk and tartness in the lime juice and gives our bars a texture similar to a light cheesecake.
- Sugar: Superfine or caster sugar is best for the brulee topping as it will caramelize nice and evenly thanks to it's fine texture.
See recipe card for quantities.
How to make Key Lime Bars:
Step 1: Crush those crackers: Crush or blend the crackers or digestives as finely as possible before adding in the melted butter.
Step 2: Press into the baking tin: Press the combined crushed cookie and melted butter into your baking tin and bake until golden.
Step 3: Filling: Beat the egg yolks and sweetened condensed milk on low until smooth. Pour in the lime juice and whip until thick and pale.
Step 4: Pour and bake: Pour over the crust and bake until golden and only slightly jiggly. Set aside.
Step 5: Cool completely: Cool and refrigerate for a minimum of 3 hours or overnight.
Step 6: Top: Cool and refrigerate for a minimum of 3 hours or overnight. Sprinkle the topping over and caramelize.
Step 8: Slice and serve: Dig in!
FAQ's for the best Key Lime Bars
Absolutely! Key limes can be difficult to obtain so you can substitute regular fresh or bottled lime juice in equal measure here.
Yes, baking helps set the crushed base and means liquid of the filling doesn't soak through that crushed biscuit base meaning it's nice and firm and can't become soggy.
Due to the amount of lime juice in this pie, baking the filling ensures the custard sets which can't always be guaranteed when it's not baked.
If you use 80 milliliters or less than โ cup of lime juice, you shouldn't have to, though this will lessen the strength of that lime flavor without using any other setting agents.
It is best to make this up to 1 day before serving, but this is best served within 2 hours of caramelizing the sugar on top of the bars as this will soften the longer they are left out.
More lime recipes you'll love
Key Lime Bars
Ingredients
Base
- 150 grams / 5.3 ounces graham crackers crushed
- 50 grams / 1.75 ounces butter melted
Filling
- 70 grams / 4 large egg yolks room temperature
- 414 milliliters / 1 can sweetened condensed milk
- 113 grams / ยฝ cup heavy cream
- 75 grams / โ cup key lime juice
- 28 grams / 2 tablespoons superfine/caster sugar
Instructions
- Preheat the oven to 190ยฐC/375F and line a 18ร18 cm or 7ร7 inch square baking tin with parchment paper.
Base
- Place the crushed biscuits and melted butter and stir until no dry portions remain in the bowl and the mixture resembles a rough breadcrumb.
- Spoon into your tin and press down firmly.
- Place in the oven and bake for 10 minutes until lightly golden.
Filling
- For the filling, place the egg yolks, sweetened condensed milk and heavy cream in a bowl and beat on low to break the egg yolks and get the mixture smooth, approximately 2 minutes.
- Add in the lime juice and beat on medium until thick and pale, approximately 2 minutes.
- Pour the into the cooled crust, cover and place in the oven until only jiggly in the center, approximately for 20 minutes.
- Remove and allow to cool completely before refrigerating for a minimum of 3 hours or overnight.
Caramelized topping
- Just before serving, slice into your bars and sprinkle over the 2 tablespoons sugar evenly on top.
- Blowtorch to caramelize or place under the broiler until bubbling and golden.
- Serve up!
Notes
- Lime juice: The very core of this recipe is the fresh lime juice which adds a bright and zesty flavor to the custard filling. Key lime juice is best, but you can replace with any other fresh lime juice.
- Heavy cream: The heavy cream balances out the sweetness in the condensed milk and tartness in the lime juice and gives our bars a texture similar to a light cheesecake.
- Why this is baked: Due to the amount of lime juice in this pie, baking the filling ensures the custard sets which can't always be guaranteed when it's not baked.
- If you donโt want to bake your bars: If you use 80 milliliters or less than โ cup of lime juice, you shouldn't have to, though this will lessen the strength of that lime flavor without using any other setting agents.
- Baking tin: A square baking tin was used, though a rectangle tin would also work well. Note, the larger the tin from the one used here, the thinner your base and filling will be.
Nutrition
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