I have been wanting to make a treat with key lime juice and I was looking for a portable treat for this past weekend for a picnic. So I decided to try lemon squares but with key lime juice instead. They turned out fantastic.
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Key limes are those tiny limes in a bag you see in the produce section or you can buy just the juice in a bottle on the juice aisle at the grocery store. I like to buy the bottled one that really comes from Key West because these days the ones in the produce section probably come from Mexico. Again you can find it in the juice aisle at the grocery store or on Amazon. Just make sure you get one that is from the Florida Keys. Real Key limes actually look like a lemon. And it would take a lot of squeezing to get this much juice from those tiny limes from the grocery store.
For the crust, I took some help from a store bought sugar cookie mix. I was making other food for the picnic and needed a shortcut. I like to keep a few mixes for cakes and cookies in my pantry for times like this. There’s no harm in getting a little help. With a few extra touches, they are as tasty as something from scratch. If you would like to make the crust from scratch or don’t have a mix on hand, check out my chewy sugar cookie recipe. Half the recipe would make a great crust for this.
To make the mix a little tastier, I subbed half of the butter with cream cheese and added extra flour and touch of vanilla extract. After mixing, I spread the cookie crust mix evenly in a lightly buttered 13×9 baking dish. I place a bit of wax paper over the top while smoothing it out then remove it before baking. It helps to keep the dough from sticking to your hands or spatula. I pushed the crust up the sides just a bit too.
I baked the crust til it was just lightly golden on the edges about 10 -12 minutes. It will cook more after its is filled and baked again too. Don’t want the edges too brown or they will during that second baking. Let the crust cool completely before filling.
For the filling, I mixed together eggs, sugar, key lime juice, flour, and vanilla. I poured the filling into the cooled cookie crust. Then baked it for about 25 minutes.
After it cooled, I sprinkled it generously with powdered sugar and sliced it up. I ended up cutting it into triangles rather than squares cause I thought it looked better in the end.
These tangy sweet treats won’t disappoint. So grab some key lime juice and get to baking!