There’s something about a pan of Key Lime Pie Bars chilling in the fridge that makes spring and early summer feel a little more settled. When the weather starts warming up and the markets fill with bright, zesty citrus, I like having a dessert that feels refreshing but still familiar and cozy. These bars hit that spot between bright and comforting: creamy, tangy, and easy to slice for whoever happens to be around the table.
I first started making these when I wanted the flavor of classic key lime pie without dealing with a fussy crust or a water bath. A simple graham cracker base, one bowl for the filling, and the oven does the rest. They’re ideal for days when you want something homemade but don’t want to hover over the stove. You can use key limes when you find them in season, but regular limes work just as well and keep the recipe flexible for local availability.
What I like most is how well these bars fit into real life: they chill while you clean up, they slice neatly for potlucks or picnics, and they keep in the fridge for a few days without losing that creamy texture. If you’re leaning into seasonal produce and trying to keep things simple and sustainable, this is a good way to let fresh lime juice do the heavy lifting. Bake a pan in the afternoon, and you’ve got a cool, citrusy dessert ready whenever you need a quiet moment or a low-effort treat to share.
Whip Up Key Lime Pie Bars
Tools of the Trade & Core Ingredients
Tools
- 8-inch square baking pan
- Parchment paper
- Mixing bowls (at least 2)
- Electric mixer with paddle and whisk attachments (or hand mixer)
- Rubber spatula
- Measuring cups and spoons
- Microplane or fine grater for zesting
- Sharp knife for slicing bars
Graham Cracker Crust
- 1½ cups gluten-free graham cracker crumbs
- 1 tablespoon granulated sugar
- ½ teaspoon ground cinnamon
- ¼ teaspoon ground nutmeg
- Pinch of salt
- 1 large egg white
- 3 tablespoons butter or dairy-free butter, melted
Key Lime Filling
- 4 oz cream cheese or dairy-free cream cheese, room temperature
- 4 large egg yolks, room temperature
- ½ cup + 1 tablespoon fresh lime juice (about 3–4 limes, depending on size)
- 2 teaspoons packed lime zest (about 2 limes)
- 1 (14 oz) can sweetened condensed milk or sweetened condensed coconut milk (for dairy-free)
The Process
- Prep the pan and oven. Heat your oven to 350°F (175°C). Line an 8-inch square pan with parchment paper, letting it hang over two sides to create handles for easy lifting later. Set the pan aside.
- Mix the crust. In a large bowl, combine the gluten-free graham cracker crumbs, sugar, cinnamon, nutmeg, and a pinch of salt. Add the egg white and melted butter. Stir or mix until all the crumbs are evenly coated and the mixture looks like slightly damp sand that holds together when pressed.
- Press the crust. Tip the crumb mixture into the lined pan. Use your fingers or the bottom of a measuring cup to press it firmly into an even layer, making sure to reach all the corners. A firmly packed crust will slice more cleanly later.
- Par-bake the crust. Bake the crust for about 10 minutes, until it’s set and just turning golden at the edges. It should smell toasty but not look dark. Remove from the oven and let it cool while you make the filling.
- Increase the oven temperature. Raise the oven temperature to 375°F (190°C) so it’s ready for baking the filling.
- Beat the cream cheese. In a large mixing bowl, use the paddle attachment of your mixer to beat the room-temperature cream cheese until it’s completely smooth and creamy. Make sure there are no lumps at this stage; they’ll be harder to fix once everything else is added.
- Add the egg yolks. Switch to the whisk attachment. Add the egg yolks to the cream cheese and whisk to combine. Once they’re incorporated, mix on medium-high for about 1 minute, or until the mixture is smooth, thick, and uniform with no visible bits of cream cheese. Mix a little longer if you still see any tiny lumps.
- Incorporate the remaining filling ingredients. Pour in the sweetened condensed milk, lime juice, and lime zest. Whisk until the mixture is fully combined, thick, and creamy. Stop to scrape down the sides and the bottom of the bowl with a spatula to catch any cream cheese hiding underneath, then whisk briefly one more time. The filling should be silky and pourable but not runny.
- Assemble and bake. Pour the filling over the cooled graham cracker crust and spread it into an even layer. Tap the pan lightly on the counter to release any air bubbles. Bake for 15–18 minutes, until the edges look set and the center still has a gentle wobble when you nudge the pan. Check at 15 minutes; if the top is browning too quickly but the center isn’t set, tent the pan loosely with foil and bake 1–2 minutes more.
- Cool and chill. Let the bars cool in the pan at room temperature for about 1 hour. Then transfer the pan to the refrigerator and chill for 2–3 hours, or overnight, until fully cold and firm. This chilling time is key for clean slices and the right creamy texture.
- Slice and serve. Use the parchment paper overhang to lift the entire slab out of the pan onto a cutting board. Use a sharp knife to cut into 16 bars, wiping the blade clean between cuts for the neatest edges. If you like, top each bar with a small dollop of whipped cream and a sprinkle of extra lime zest just before serving.
- Store the leftovers. Place any leftover bars in a sealed container and keep them in the refrigerator for up to 4 days. They’ll stay creamy and refreshing, making them easy to pull out for quick desserts or snacks.
Dairy-Free and Gluten-Free Swaps
These Key Lime Pie Bars are easy to adapt if you’re baking for mixed dietary needs. For a gluten-free crust, use certified gluten-free graham crackers and double-check that your spices are labeled gluten-free. Press the crust firmly so it doesn’t crumble; gluten-free crumbs can be a bit more delicate. If you’d like the bars completely dairy-free, choose a dairy-free cream cheese that’s neutral in flavor and not too soft, plus sweetened condensed coconut milk in place of regular condensed milk. Expect a very slight coconut note, which pairs nicely with lime. For the butter, use a plant-based baking butter stick rather than a soft spread so the crust sets properly. Always chill the bars thoroughly so both gluten-free and dairy-free versions hold their shape when sliced.
Getting the Creamiest Filling
The key to a really creamy lime filling is managing temperature and texture from the start. Make sure both the cream cheese and egg yolks are at room temperature; cold ingredients are the most common cause of tiny lumps that won’t whisk out. Take a moment to beat the cream cheese alone until completely smooth before adding anything else. When you mix in the yolks, avoid overwhipping to the point of foamy bubbles, which can lead to a slightly airy, less silky texture. After adding the sweetened condensed milk and lime juice, whisk just until everything is evenly combined and glossy. If you see stubborn specks of cream cheese, stop and scrape the bowl, especially the bottom. Finally, don’t overbake: pull the bars when the edges are set but the center still has a gentle jiggle. Overbaking can make the filling grainy instead of smooth.
How to Slice Clean Bars
Clean, sharp slices make these bars feel more put-together, especially if you’re bringing them to a gathering. Start by letting the bars chill until they’re fully cold and firm; cutting too soon is the fastest way to get messy edges. Lift the entire slab out of the pan using the parchment overhang so you’re working on a cutting board, not in the pan itself. Use a long, sharp knife and run it under hot water, then dry it before each cut. Press down in a single, confident motion instead of sawing back and forth. Wipe the blade clean and rewarm it between cuts. For perfectly even pieces, you can lightly score the top to mark your cuts before slicing all the way through.
Recipe Help: Frequently Asked Questions
Can I make these Key Lime Pie Bars ahead of time for an event?
Yes, these bars are very make-ahead friendly, which is helpful if you’re planning for a gathering. You can bake them up to 24–36 hours in advance. Once they’re fully chilled and sliced, place the bars in a single layer in an airtight container, or separate layers with parchment so they don’t stick. Wait to add whipped cream or extra lime zest until just before serving to avoid weeping or discoloration. If your fridge tends to be very cold, let the bars sit at room temperature for about 10–15 minutes before serving so the filling softens slightly but still stays firm.
What if I only have bottled lime juice instead of fresh?
Fresh lime juice is ideal here, especially if you’re following seasonal eating and want that bright flavor, but bottled juice can work in a pinch. If you use bottled, choose a brand that’s 100% lime juice with no added sweeteners. Keep the zest from at least one fresh lime, if possible, because the oils in the zest contribute a lot of aroma and flavor that bottled juice can’t provide. You may notice a slightly flatter, less vibrant taste with bottled juice, so don’t skip the zest and consider adding an extra ½ teaspoon for brightness. Always shake bottled juice well before measuring to ensure the flavor is consistent.
Why did my crust turn out crumbly or too hard?
If your crust crumbled when slicing, or turned out overly firm, it usually comes down to either moisture or packing. A crust that’s too dry may not have enough butter or egg white to bind the crumbs; next time, make sure the mixture looks like slightly wet sand that holds together when pinched. On the other hand, pressing the crust too firmly can make it dense and hard once baked, especially with gluten-free crumbs. Aim for even, moderate pressure—firm enough that it doesn’t shift, but not so tight that it compacts into a solid layer. Also, keep an eye on bake time: overbaking the crust before adding the filling can dry it out and make it tough.
Key Lime Pie Bars
Equipment
- 8-inch square pan
- parchment paper
- Mixer (stand or hand)
- Mixing bowls
- spatula
Ingredients
Graham Cracker Crust:
- 1 1/2 cups gluten-free graham cracker crumbs
- 1 tablespoon granulated sugar
- 1/2 teaspoon ground cinnamon
- 1/4 teaspoon ground nutmeg
- pinch salt
- 1 large egg white
- 3 tablespoons butter or dairy-free butter melted
Key Lime Filling:
- 4 ounces cream cheese or dairy-free cream cheese room temperature
- 4 large egg yolks room temperature
- 1/2 cup + 1 tablespoon lime juice about juice of 3–4 limes
- 2 teaspoons lime zest packed (zest of 2 limes)
- 1 14 ounce can sweetened condensed milk or sweetened condensed coconut milk
Instructions
- Gather all ingredients and line an 8-inch square pan with parchment paper; set aside.
Graham Cracker Crust:
- Preheat the oven to 350°F (175°C). Prepare the pan by lining it with parchment.
- Combine the graham cracker crumbs, sugar, cinnamon, nutmeg, and salt in a bowl. Stir in the egg white and melted butter until the mixture holds together.
- Press the crumb mixture evenly into the prepared pan to form a compact layer.
- Bake the crust about 10 minutes, until set and lightly golden. Remove from the oven and allow it to cool while you prepare the filling.
Key Lime Filling:
- Increase the oven temperature to 375°F (190°C).
- In a large bowl, beat the room-temperature cream cheese with the paddle or a mixer until smooth and creamy.
- Add the egg yolks and beat with the whisk or paddle attachment until fully incorporated and the mixture is smooth—about 1 minute—scraping the bowl as needed to eliminate lumps.
- Pour in the sweetened condensed milk, lime juice, and lime zest. Whisk thoroughly, scraping the sides and bottom, until the filling is thick, silky, and uniform.
- Pour the filling over the cooled crust and return to the oven. Bake 15–18 minutes, until the edges are set and the center still has a slight wobble. Check at 15 minutes and cover loosely with foil if it needs a minute or two more.
- Allow the bars to cool in the pan for about 1 hour, then transfer to the refrigerator to chill for 2–3 hours or overnight for best texture.
- Lift the bars from the pan using the parchment, slice into serving pieces, and top with whipped cream and extra lime zest if desired.
- Store leftovers in an airtight container in the refrigerator for up to 4 days.