You’ve all (I assume) had lemon bars before, but today we’re talking about lemon bars’ vibrant twin…LIME BARS.
That’s right, shortbread cookie flavored crust topped with an incredible, sweet-and-tart custard lime filling baked and chilled to perfection. These lime bars are the ultimate summertime treat that seriously taste like a slice of key lime pie! Yes, they can easily be made gluten-free and dairy-free, too!
These beautiful lime bars are easier to make than you think, but take a bit of time and care, so be sure to read through the instructions, any substitutions, and all of my tips as you start baking. I hope you love them as much as we do!
Everything you’ll need to make these lime bars
These beauties are bursting with lime flavor, but have the perfect amount of sweetness. Here are the simple ingredients you’ll need:
- Sweetener: you’ll need granulated sugar for the lime custard filling, and a little pure maple syrup to sweeten the shortbread base.
- Lime: these bars pack plenty of that key lime pie flavor (but I use regular limes). You’ll need both fresh lime juice and lime zest.
- Eggs: we’re using four whole eggs (not just egg yolks) in the creamy filling to help achieve the custard-like texture.
- Flour: a little all-purpose flour helps set the filling, and fine blanched almond flour creates the shortbread crust.
- Butter & oil: you’ll need a couple tablespoons of salted or unsalted butter for the filling, plus a little coconut oil in the crust to help both set well with the right amount of moisture.
- Baking staples: don’t forget the vanilla extract and salt in the base!
- For topping: I like to top the bars with powdered sugar and extra lime zest for a pretty look.
Add extra green color
If you want to make the filling a brighter green color, feel free to add a drop of green food coloring! Usually, 1-4 drops work well. I like to use artificial dye-free food coloring. This is, of course, optional.
Can I make them gluten-free?
Yes! Simply swap the all-purpose flour in the filling for 1:1 gluten-free all purpose flour.
What about vegan or dairy-free?
You can replace the butter in the filling with vegan butter to keep the lime bars dairy-free, but please note that these bars cannot be made vegan because I do not have a substitute for the eggs in the filling.
How to make the best lime bars
- Mix the filling. Use clean fingers to rub together the lime zest and sugar in a medium pot to infuse the sugar with lime flavor. Whisk the lime-sugar mixture in the pot with lime juice, eggs, and flour, then set it aside.
- Bake the crust. Mix all of the crust ingredients in a medium mixing bowl until a thick crumb texture forms. Press the dough into an 8×8 inch pan lined with parchment paper, and bake until slightly golden brown on the edges.
- Cook the filling. While the crust is cooking, place the pot with the filling over medium-low heat and whisk constantly until the mixture thickens. Pour the filling through a mesh sieve over a medium bowl and mash it through the strainer with a spoon.
- Bake the bars. Stir the butter into the warm filling until melted, and add food coloring (if using). Pour the mixture over the warm crust and spread evenly with a spatula. Bake bars until the filling is set.
- Cool (then cool again). Let the bars cool to room temperature for 1-2 hours, then refrigerate for at least 2 hours.
- Top & serve. Dust the bars with powdered sugar and sprinkle extra lime zest, then slice using a clean, sharp, wet knife and serve!
Don’t forget these helpful tips
Lemon and lime bars can be a little bit tricky because of how soft the filling is, but with these easy tips, you’ll have perfect lime bars every time:
- Use the right pan. Be sure to use an 8×8-inch pan, not a 9×9, because a 9-inch pan will make the bars too thin.
- Whisk the eggs completely. When you whisk your eggs into the filling mixture, make sure to do so until there are no white streaks. Otherwise, you may end up with white streaks in the bars after they’re baked.
- Add the filling to WARM crust. Don’t let the crust cool to room temperature before adding the filling; otherwise, the filling may seep into the crust, and pieces of the crust may float into the filling layer.
- Don’t overbake. Overbaking the lime bars may cause them to crack on the tops.
- Cool, then refrigerate. Be sure to cool the bars completely to room temperature before refrigerating them. Otherwise, the tops may crack from the temperature change.
The key to slicing lime bars
Because the filling in lime bars is soft, you’ll want to slice them into bars using a wet, sharp knife (as I mentioned). Clean and wet the knife after each slice to ensure that the bars cut into neat squares!
Recommended tools for this recipe
See more of our go-to kitchen essentials here!
How to store & freeze lime bars
- To store: place leftover lime bars in an airtight container and place in the refrigerator for up to 4 days. If you are stacking the bars, add a sheet of parchment paper in between the layers to prevent sticking. You will likely need to add additional powdered sugar on top of the bars before serving, as it may dissolve into the bars in the fridge.
- To freeze: wrap the bars well and place them in a freezer-safe bag or container before putting them in the freezer and simply let them thaw in the fridge before enjoying. They should stay good in the freezer for up to 2 months.
More bars & brownies you’ll love
- Blueberry Pie Bars with Oatmeal Crumble (vegan & gluten free)
- Sweet and Salty Chocolate Tahini Rice Krispie Treats
- Raspberry Bars with Oatmeal Cookie Crumble
- The Best Zucchini Brownies You’ll Ever Eat
- Tahini Monster Cookie Bars
Get all of my bar recipes here!
I hope you love these vibrant lime bars! If you make them, be sure to leave a comment and a rating so I know how you liked them. Enjoy, xo!
Ambitious Kitchen
Cookbook
125 Ridiculously Good For You, Sometimes Indulgent, and Absolutely Never Boring Recipes for Every Meal of the Day
Vibrant Lime Bars
Ingredients
- For the lime base:
- 1 cup (200g) granulated sugar
- 2 tablespoons lime zest
- ½ cup (100g) fresh squeezed lime juice (you’ll need 6 to 10 limes, depending on how big the limes are)
- 4 large eggs
- ¼ cup (30g) all-purpose flour*
- 2 tablespoons salted butter (or vegan butter), at room temperature
- 1 to 4 drops of artificial dye-free green food coloring (optional, to get a bright green color)
- For the shortbread base:
- 1 ½ cups (168g) fine blanched almond flour
- 3 tablespoons melted coconut oil (or sub melted vegan butter or regular butter)
- 2 tablespoons pure maple syrup
- 1 teaspoon vanilla extract
- ¼ teaspoon salt
- For serving:
- Powdered sugar, for dusting
- Additional lime zest, optional
Instructions
- Preheat the oven to 350 degrees F. Line an 8x8 inch square pan (DO NOT USE 9x9 inch as it will be too big). NOTE: It’s important to use an 8x8 inch as a 9x9 inch pan may be too big.
- In a medium pot, add the sugar and lime zest and use clean fingers to rub the mixture together for about 30 seconds so the lime releases into the sugar and infuses it with flavor. Next, add the lime juice, eggs, and flour and whisk together until the mixture is well combined and no streaks of egg remain. Do not add in the butter or food dye yet. Set the pot aside.
- In a medium bowl, add the almond flour, coconut oil, maple syrup, vanilla extract and salt. Mix together with a fork until it forms a nice thick crumb texture. Add to the pan and use your fingers to evenly press down into the pan. Bake for 8-9 minutes until the crust is slightly golden brown on the edges. Remove from the oven and set aside to cool for 5 minutes. Keep heat in the oven.
- While the crust cooks, place the pot over medium-low heat and whisk constantly until the mixture thickens and coats the back of a spoon, about 6 to 8 minutes. Once the mixture has thickened, remove from heat.
- Place a sieve (fine mesh strainer) over a medium bowl. Pour mixture into the sieve and use a spoon to work and mash down the filling through the stainer.
- In the bowl with the warm lime filling, stir in the butter until melted and a few drops of green food dye to achieve a vibrant green color, if desired. Immediately pour the mixture over the warm crust and tilt the pan or spread with a spatula to evenly distribute the lime filling. Place the pan back in the oven and bake for another 8 to 11 minutes until the filling is set and barely jiggly when the pan is gently shaken.
- Allow bars to cool at room temperature for 1 to 2 hours, then transfer to the fridge and chill for at least 6 hours or up to 2 days.
- Dust with powdered sugar and cut into 16 bars using a clean, sharp, wet knife. Clean and wet the knife after each cut. Annoying, but it helps to get the perfect cut! Add a little extra lime zest on top if you want a little extra zing.
- To store: Place leftover bars in an airtight container and place in the fridge for up to 4 days. If you are stacking the bars, add a sheet of parchment paper in between the layers to prevent sticking. You will likely need to add additional powdered sugar on top of the bars before serving as it may dissolve into the bars in the fridge.
Recipe Notes
Nutrition
Recipe by: Monique Volz // Ambitious Kitchen | Photography by: Eat Love Eats
This post was originally published on July 9th, 2024, updated with a video on June 16th, 2026, and republished on June 21st, 2026.
Amazing. Sweet and tangy. Perfect to take on a summer picnic.
Absolutely! Such a great summer treat.
CAN U USE A GRAHAM CRACKER CRUST FOR THE LIME BARS ? THANK u
Yes that sounds delicious!
Hi!
Do you think I can use cornstarch instead of flour for the lime filling? Thanks
Hi! I haven’t tested it, so I’m not 100% sure how the texture will change.