Key Lime Bars
Add Preferred SourceIf you’re in the mood for something bright, creamy, and just the right amount of sweet, these Key Lime Bars deserve a spot on your table. Built on a buttery graham cracker crust and layered with a smooth, tangy key lime filling, they deliver a refreshing bite that’s hard to resist. Enjoy them with whipped cream or plain—either way, they’d keep you reaching for another slice.
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During summer, when the days are long and the gatherings are easygoing, these refreshing treats fit perfectly—whether it’s a picnic, cookout, or lunch. I can make them ahead, stash them in the fridge, and not think twice until it’s time for dessert. You can also freeze them, which is perfect if you want to stretch out the extras a little longer.
Ingredients You’ll Need
You’ll need all the ingredients shown in the photograph below.
How to Make Key Lime Pie Bars with Step-By-Step Instructions
Scroll down for the full recipe card containing a full printable recipe and measurements in both US customary and metric units.
By following my simple steps, you’ll find making these key lime bars easy and rewarding.
Prepare the Crust
In a medium bowl, stir together the graham cracker crumbs, sugar, and melted butter until everything looks evenly coated.
Press the crumb mixture firmly into an 8×8-inch square baking pan or baking dish, lined with parchment paper, using the flat bottom of a measuring cup to make an even layer that’s packed tight and doesn’t crumble.
Bake the Crust
Place the pan on a baking sheet to catch any drips and bake in a preheated oven at 350°F (180°C) for about 10 minutes.
Once it’s lightly golden, remove the pan from the oven and let it cool slightly while you prepare the filling.
Lower the oven temperature to 325°F (160°C). Dropping the temperature helps the creamy key lime layer bake more gently, so it stays silky and smooth without overcooking or cracking.
SERIOUSLY GOOD
DESSERTS!
Dessert First is a collection of 61 RECIPES to show you that you can make beautiful, impressive desserts right in your own kitchen, no matter your skill level.
Immediate eBook download. No physical book available.
∙ Lemon Pound Cake
∙ Starbucks Cake Pops
∙ Boston Cream Pie
∙ Chocolate Mousse
∙ Matcha Tiramisu
...and much more!
Includes ad-free recipes like:
Make the Key Lime Filling
In a clean large bowl, whisk the egg yolks, sweetened condensed milk, fresh lime juice, key lime zest, sour cream, and a pinch of salt.
Keep whisking until the filling looks completely smooth and creamy with no streaks.
Assemble and Bake
Pour the key lime filling over the slightly cooled Graham crackers crust, spreading it out into an even layer. Bake for 20 minutes, or just until the edges are set; the center should still have a little jiggle when you gently move the pan.
That little bit of movement in the center means the filling will finish setting as it cools, staying creamy and smooth instead of becoming dry or overbaked.
Cool and Chill
Let the bars cool completely on a wire rack for about 2 hours. Once they’re no longer warm to the touch, transfer them to the fridge and chill for at least an hour if you like a firmer, colder texture.
Top and Slice
Before serving, spread or pipe whipped cream over the top of your chilled key lime bars if you want it extra creamy. Slice into squares using a sharp knife for clean edges.
Finally, serve and enjoy!
Ingredients
For the crust:
- 1 ½ cups graham cracker crumbs
- 2 tablespoons white sugar
- 5 tablespoons unsalted butter melted
For the key lime pie:
- 3 large egg yolks
- 1 ⅓ cups sweetened condensed milk
- ½ cup key lime juice
- 1 tablespoon key lime zest
- 1 tablespoon full-fat sour cream
- Pinch of salt
- ½ cup whipping cream to serve
Instructions
- Preheat oven to 350°F (180°C).
- In a medium bowl, combine graham cracker crumbs, sugar, and melted butter. Mix with a fork until evenly moistened. Press the mixture firmly into an 8×8-inch baking pan using the bottom of a measuring cup.1 ½ cups graham cracker crumbs, 2 tablespoons white sugar, 5 tablespoons unsalted butter
- Place the pan on a baking sheet and bake for 10 minutes. Remove from oven and let the crust cool slightly. Lower oven temp to 325°F (160°C).
- In a clean bowl, whisk together egg yolks, sweetened condensed milk, key lime juice, zest, sour cream, and salt until smooth and creamy. Pour the filling over the slightly cooled crust and spread evenly.3 large egg yolks, 1 ⅓ cups sweetened condensed milk, ½ cup key lime juice, 1 tablespoon key lime zest, 1 tablespoon full-fat sour cream, Pinch of salt
- Bake for 20 minutes, or until the edges are set and the center has a gentle jiggle.
- Let the bars cool completely on a wire rack (about 2 hours). Chill in the fridge if you like them extra cold!
- Top with whipped cream and slice into squares before serving.½ cup whipping cream
Notes
- Tightly Pack the Crust: Use a measuring cup to firmly press down the crust so it doesn’t fall apart when you lift or slice the bars.
- Use Fresh Key Lime Juice: If you can find fresh key limes, squeeze them! The bright flavor makes a real difference compared to bottled juice.
- Whisk Thoroughly: Make sure the filling mixture is fully combined and smooth before pouring it over the crust for the best texture.
- Watch the Baking Time: You want the edges set but the center to still have a slight wiggle—that’s when you know they’re perfectly creamy inside.
- Cool Gradually: Let the bars cool on a wire rack before chilling to avoid too much condensation, which can make the crust soggy.
- Chill for Cleaner Slices: Cold bars slice more neatly, so give them a good hour in the fridge if you want sharp squares.
- Top Right Before Serving: Add the whipped cream just before you serve to keep it looking fresh and fluffy.
- Warm Your Knife for Slicing: Dip a sharp knife in hot water, wipe it dry, and slice for smooth, clean cuts.
Nutrition
SERIOUSLY GOOD
DESSERTS!
Dessert First is a collection of 61 RECIPES to show you that you can make beautiful, impressive desserts right in your own kitchen, no matter your skill level.
Immediate eBook download. No physical book available.
∙ Lemon Pound Cake
∙ Starbucks Cake Pops
∙ Boston Cream Pie
∙ Chocolate Mousse
∙ Matcha Tiramisu
...and much more!
Includes ad-free recipes like:
Recipe Notes and Expert Tips
I’ve learned a few tricks over the years that I’ll share with you, so your key lime bars turn out as great as possible:
- Tightly Pack the Crust: Use a measuring cup to firmly press down the crust so it doesn’t fall apart when you lift or slice the bars. You can use a food processor to make fine crumbs.
- Use Fresh Key Lime Juice: If you can find fresh key limes, from Florida Keys, squeeze them! The sweet flavor makes a real difference compared to bottled juice. If you can’t track them down regular limes will work, they just won’t have quite the same taste.
- Whisk Thoroughly: Make sure the filling mixture is fully combined and smooth before pouring it over the crust for the best texture.
- Watch the Baking Time: You want the edges set but the center to still have a slight wiggle—that’s when you know they’re perfectly creamy inside.
- Cool Gradually: Let the bars cool on a wire rack before chilling to avoid too much condensation, which can make the crust soggy.
- Chill for Cleaner Slices: Cold bars slice more neatly, so give them a good hour in the fridge if you want sharp squares.
- Top Right Before Serving: Add the whipped cream just before you serve to keep it looking fresh and fluffy.
- Warm Your Knife for Slicing: Dip a sharp knife in hot water, wipe it dry, and slice for smooth, clean cuts.
How to Store Leftovers
Key Lime Bars are best stored in an airtight container in the refrigerator. They’ll stay fresh for up to 5 days.
If you want to keep them longer, you can freeze them for up to 3 months. Just skip the whipped cream topping until you’re ready to serve, and wrap the bars in plastic wrap or aluminum foil before placing them inside a freezer-safe bag. Thaw them overnight in the refrigerator before serving.
What to Serve With Key Lime Bars
You can pair these key lime bars with a handful of fresh berries for an extra pop of color, a scoop of vanilla ice cream to keep things classic, or a simple cup of coffee or tea if you’re in the mood for something cozy and light.
Their citrusy, refreshing flavor also plays really well with tropical fruits like mango or pineapple if you want to brighten up your dessert spread even more.
More Easy Dessert Recipes for You to Try at Home
I have plenty of easy, crowd-pleasing, and refreshing desserts that you can whip up any time you want something homemade and delicious, like the ones below:
