One bite of these creamy, tart, and perfectly sweet Key Lime Pie Bars puts me in tropical vacation mode—FAST! Since a dreamy vacation to the Keys was not in the cards this year, these bars have been in regular rotation at my house all summer. The buttery base is loaded with Ritz crackers, brown sugar, AND graham crackers for the ultimate easy crust, while the key lime filling is velvety smooth and creamy thanks to the addition of Greek yogurt. These homemade bars are like a slice of paradise– I guarantee you’ll want to make a double batch!
What is Key Lime Pie?
Key lime pie is a classic American dessert made from key lime juice, sweetened condensed milk, and a crumbly cracker crust. Its origins are hotly contested; some say this deliciously tart treat originated in the kitchens of New York City, while others more widely believe it was first made in Key West, Florida, where key limes grow in abundance. No matter where it originated, my key lime pie bar recipe gives you all the flavors of this iconic dessert in an easy-to-make and portable form!
Key limes are smaller than regular limes, and their flavor is more bitter. They’re also more aromatic and have a lighter, more yellow juice than regular limes. If you can find some fresh, a thin slice will make the perfect garnish! In my recipe, I opted for regular lime juice over key lime, because it shaved about $3.00 off my total cost, and, as you know, that’s what we’re all about here in the Budget Bytes kitchen.
Ingredients for Key Lime Pie Bars
Here’s what you’ll need to make these homemade key lime pie bars:
- Ritz Crackers: These buttery, salty crackers make the crust extra delicious.
- Graham Crackers: Use whole graham crackers, rather than the pre-made boxed crumbs, to cut costs and give the crust a better texture.
- Brown Sugar: Adds sweetness and helps to bind the crust together.
- Butter: Use cold, unsalted butter to make the crust.
- Cornstarch & Water: Helps to thicken the key lime filling without using eggs.
- Lime Juice: I use regular lime juice because it’s easy to find and budget-friendly. Feel free to use key lime juice if you can! Nellie and Joe’s key lime juice is a great option if you have some extra room in your budget!
- Lime: As I use regular lime juice (which is sweeter than key lime juice), the zest and juice from a fresh lime add a little extra zing.
- Greek Yogurt: Adds tang and creaminess to the filling. Use full fat Greek yogurt for the best results. The yogurt also helps give it a custardy texture, so I don’t miss eggs in my version of this recipe!
- Sweetened Condensed Milk: Makes this key lime pie bars recipe extra creamy and sweet.
Is Key lime pie supposed to be yellow or green?
Believe it or not, key lime pie is supposed to be yellow! Key lime juice, by nature, is a pale yellow color, meaning the filling of a traditional key lime pie will also be yellow. Green key lime pies have added food coloring or additional ingredients to achieve the green color. So don’t worry if your homemade key lime pie bars look yellow instead of green—that’s how they should be!
Storage Instructions
Keep your key lime squares in an airtight container in the refrigerator for 3-4 days. The crust may soften slightly after a few days, but they’ll still taste delicious! These bars also freeze really well. Lay them out in a single layer on a baking sheet and freeze for an hour, then transfer to a freezer-safe container for up to 3 months. Thaw in the refrigerator overnight before serving.
How To Get Clean Slices
I know how delicious these key lime pie bars smell fresh out of the oven, and it can be tempting to cut into them right away! However, for the best results, wait until they’ve cooled and then chill in the refrigerator for 30 minutes to an hour before cutting. Use a sharp knife and cut straight down in one motion, wiping the knife clean between each slice. This will give you beautiful, clean edges and slices that hold their shape.
Key Lime Pie Bars
Servings 15 bars, 1 square per personIngredients
Crust Ingredients
- 15 ritz crackers* ($0.55)
- 9 sheets of Graham crackers (1 package)** ($0.74)
- 4 Tbsp unsalted butter ($0.49)
- 3 Tbsp brown sugar ($0.09)
Filling Ingredients
- 2 Tbsp cornstarch ($0.10)
- 2 Tbsp cold water ($0.00)
- 1 lime, zest + juice*** ($0.25)
- ¾ cup lime juice ($0.49)
- ¼ cup full fat Greek yogurt ($1.02)
- 2 14 oz. cans sweetened condensed milk ($4.46)
Instructions
- In a food processor, combine Ritz crackers, graham crackers, unsalted butter, and brown sugar.
- Pulse until well-combined, but not too fine!
- Press crust evenly into parchment-lined 9×13” baking dish.
- Bake crust for 15 minutes at 350°F. Remove from oven and let cool.
- Gather cornstarch, cold water, lime juices, lime zest, Greek yogurt, and sweetened condensed milk. Whisk cornstarch and cold water together.****
- Whisk all key lime filling ingredients together in a large mixing bowl until smooth.
- Pour key lime filling on top of pre-baked crust.
- Bake for another 15 minutes at 350°F. Remove from oven, allowing it to cool completely.
- Pop it in the fridge for 30 minutes to an hour. Then, slice bars into squares and (optional) serve with a dollop of homemade whipped cream or Cool Whip! Enjoy.
See how we calculate recipe costs here.
Notes
Nutrition
how to make Key Lime Pie Bars – step by step photos
In a food processor, combine 15 Ritz crackers, 9 sheets of Graham crackers, 4 Tbsp of unsalted butter, and 3 Tbsp of brown sugar.
Pulse until well combined, but not too fine!
Press crust evenly into parchment-lined 9×13” baking dish. Bake crust for 15 minutes at 350°F. Remove from oven and let cool.
Gather 2 Tbsp cornstarch, 2 Tbsp cold water, ¾ cup of lime juice, the additional juice and zest from 1 lime, ¼ cup of full fat Greek yogurt, and 2 14 oz. cans of sweetened condensed milk. Whisk cornstarch and cold water together.
Whisk all key lime filling ingredients together in a large mixing bowl until smooth.
Pour key lime filling on top of pre-baked crust.
Bake for another 15 minutes at 350°F. Remove from oven, allowing it to cool completely.
Pop it in the fridge for 30 minutes to an hour. Then, slice bars into squares and (optional) serve with a dollop of homemade whipped cream or Cool Whip! Enjoy.
This recipe for key lime pie bars is bright, tangy, and refreshing—perfect for summertime!
This turned out delicious! I was a little confused about the lime in the directions… I tried to make exactly as directed but bought key limes instead of regular limes. So I zested and juiced a few key limes to be roughly the equivalent of one lime, and then had regular lime juice in the fridge. It turned out great. If you like a lot of graham cracker crust like we do, it might be worth it to double the crust or put it in a smaller pan and adjust. The crust layer is pretty thin for our taste in a 9×13 pan. I was also confused about what to do with the butter, I wasn’t sure if it needed to be room temp, cold, or if it mattered. Might not hurt to put that in the recipe! And I don’t know if there is a way to make the lime portion a little easier to understand? Maybe it was just me assuming I should buy key limes since it was in the name! Regardless, this was delicious and I will be making it again.
Key limes are traditionally used, but at Budget Bytes, we try to prioritize using cost-effective and easy-to-find ingredients, so regular limes are used in our recipe. Regular limes are a bit sweeter than key limes, but I’m glad to hear your flavor was still good! Thanks for making the recipe and sharing your feedback!
Pro tip: if you’re abroad and don’t have access to graham crackers (which appear to be unabashedly American), digestive biscuits work well! They’re not as dry as graham crackers so may need to adjust accordingly.
For people outside of the US who can’t get graham crackers, how much in grams would that be? It’s kind of hard to work out if you don’t know what a sheet of graham crackers is like, but my guestimate from what I can find online would be about 135grams? Is that right?
(I am a strong encourager of using grams/ml conversions in recipes wherever possible for ease of use – I gotta admit, I often have to do maths before I can use most Budget Byte recipes, as much as I love them!)
Unfortunately, we haven’t found a good solution for this yet! There are a lot of plugins and apps that already do automatic conversion (the recipe card that we use actually has that functionality), but while it sounds great in theory, it rarely works well in practice. There are many issues that prevent it from working properly, one of the main reasons being that often you need to not only convert from imperial to metric, but you also need to convert from volume to weight, which requires knowing the density of that particular ingredient. Other big issues include inconsistent ingredient formatting, the fact that we use both weight and volume ounces, and ingredients that contain both solid and liquid material, but the containers only list the “dry” weight. We’ve explored the issue a lot and just don’t feel comfortable offering metric units unless we can manually remeasure and test each recipe with those units. Right now that’s not feasible, BUT hopefully in the future, when we have a full team, that’s a project we can put on the list. That being said, you’re correct! It *should* be roughly 130-135 grams for the graham cracker portion.
Thanks! I appreciate the complexities and I’m glad you’re considering it.
I made this recipe and it turned out great! Definitely have to wait for it to cool all the way before slicing, as otherwise the base was a bit crumbly, but after a couple of hours it was fine.
I used McVities Digestive biscuits instead of Graham crackers and my ingredient measurements worked out to the following in grams (including remembering to use US cups and tablespoon measures, because US/UK/Australia are all different!):
135g digestive biscuits
15 Ritz crackers (you can get these everywhere, so didn’t need to weigh)
56grams butter
17grams brown sugar
28grams cornstarch
28grams cold water
Juice and vest of one lime (didn’t weigh these)
180ml lime juice
60g yoghurt
2x 400g cans of sweetened condensed milk (this is very slightly more than the direct ounce conversion, but sweetened condensed milk is sold in 400g cans so makes sense to use the whole lot)
I’ll try to post the conversions to the recipes I’ve tried and maybe that will help out :)
Caroline, love the substitution you made for the crust. Yum. Thanks for sharing your experience– super helpful for sure.
This recipe looks amazing! Can’t wait to try it. My lazy self wonders if a store-bought graham cracker crust would work??? Thank you in advance! :)
We only tried with the homemade crust (and I have to say, the ritz crackers add a lovely buttery saltiness). If you did try it, you’d likely have to split it between two crusts as it would be too much filling for one, and the cooking time would also likely be much less. But you could definitely experiment and let us know how it goes!
How many digestives was your equivalent?
Do these keep well in the freezer? They look great 😊
Oooh no egg!? Love this option.
So good. You won’t miss ’em! I hope you enjoy.
I love Key Lime!! This is such an easy prep recipe from start to finish. Very refreshing and delicious!
So glad you enjoyed! Thanks.