These Key Lime Cookies are soft and buttery with a zesty, melt-in-your-mouth flavor from key limes. They're the perfect sweet-tart combination that is just as delicious in summer as it is around Christmas time. And don't be surprised when they disappear as quickly as you can make them!
Having lived in Florida for over 38 years I'm totally obsessed with anything key lime. From my Key Lime Smoothies for breakfast to tropical Key Lime Cocktails for happy hour to authentic Key Lime Pie for dessert, I never get tired of its zesty, refreshing taste.
One of the easiest ways to get my key lime fix is by whipping up these melt-in-your-mouth, citrusy Key Lime Cookies. It's amazing how much they taste like those packaged Key Lime Coolers you buy in Key West. And they're just as tart, delicious, and tender too!
Table of contents
Ingredients
- Butter - is a must in cookies, adding moisture and helping with leavening. A high quality butter is important since it lends delicious flavor to the overall baked goods.
- Sugars - aside from sweetening the cookies also adds texture and keeps the cookies soft and moist.
- Eggs - are a binding agent as well as a leavening agent. While the whites add moisture and stability, the egg yolks contribute to texture and flavor.
- Vanilla Extract - enhances all the flavors in baked goods much like salt does to savory recipe. Forgetting to add that warm vanilla flavor will leave the cookies tasting flat.
- Flour - holds all the ingredients together.
- Cornstarch - helps create a more tender, lighter cookie. It reduces the gluten in cookies, much the same way as pastry flour does, and you'll be amazed at the results.
- Baking Powder - helps this cookie to rise
- Salt - enhances the flavor, bringing out the zesty lime.
- Key Limes - make a big bold difference in these cookies. They have more tangy flavor that Persian limes and give the cookies a more citrusy taste. If you can't find fresh key limes, use key lime juice. I like Nellie & Joes Key West Key Lime Juice. Find more info about he difference between Persian limes and Key Limes in my Key Lime Pie post.
- Key Lime Zest - don't skip this ingredient! The zest adds a big punch of flavor to the batter. If you can't find key limes, add persian lime zest as an alternative.
Pro Tip: To try cornstarch in other cookies (it makes chocolate chip cookies even more incredible) just remove 2 Tablespoons of flour for each cup in the recipe and add 2 Tablespoons of cornstarch instead.
Frequently Asked Questions
Always try to use fresh for the best flavor but if you can't find key limes use a bottled key lime juice like Nellie & Joes. If that is unavailable, you can use ½ Persian lime juice with ½ lemon juice to give the tart flavor a boost.
They will keep about 2 weeks in an airtight container on the counter. Of course, don't be surprised if they disappear way before that!
They were probably overbaked. You want to take them out of the oven before they start to turn brown. They will still be very white in color but 16 minutes is plenty of time for them to bake.
Shortbread cookies have no leavening or eggs and are a much denser, more buttery cookie. On the other hand, sugar cookies are lighter, crisper cookies with a higher ratio of flour to fat.
Cornstarch helps to create a more tender, lighter cookie. It reduces the gluten in cookies, much the same way as pastry flour does. The results will amaze you!
Variations
- Lime Basil Cookies - Add 4 teaspoons of basil to the cookie dough and cook as directed. The basil imparts a nice herbal flavor that complements the zesty key lime.
- Key Lime White Chocolate Cookies - If you love chocolate, go ahead and add ¾ cup of white chocolate chips to the dough. It makes these buttery cookies even more indulgent. Or melt it and just drizzle it on the top!
- Love even more lime flavor? Add a lime glaze by mixing ¾ cup powdered sugar with 3 Tablespoons of key lime juice. Drizzle on cooled cookies then sprinkle a little extra zest on top.
- Love any citrus flavored cookies? Try this same recipe by replacing the key lime juice and zest with either lemons or oranges.
- Key Lime Coconut Cookies - make this lime cookie recipe even more tropical by adding ½ cup coconut to dough.
How to Make Key Lime Cooler Cookies
Gather the ingredients. Make sure the butter is at room temperature for easier whipping.
- In a large bowl, beat butter with granulated sugar and 1 cup of powdered sugar until it is light and fluffy, about 3 minutes. Take note that you can also add the 4 teaspoons of lime zest to this step to ensure it is more evenly distributed.
- Continue beating while adding eggs and vanilla extract.
- Combine the dry ingredients, flour, cornstarch, baking powder and salt, in a medium bowl.
- Beat the dry ingredients into the creamed mixture with the mixer on a low speed.
- Alternate with the key lime juice and 4 teaspoons of lime zest (if you have not already added it).
- The cookie dough batter is ready for scooping onto the cookie sheets.
- Scoop dough onto cookie sheets lined with parchment paper. Bake.
- While cookies are baking, in a large plastic bag, mix remaining lime zest into powdered sugar.
- Let baked cookies cool on cookie sheet for about 3 minutes.
- Place a few warm cookies into lime powdered sugar.
- Toss to coat then carefully remove and place on wire racks to cool.
Now, about 35 minutes later, it's time to scarf down some of the best key lime cookies you've ever tasted!
Just look at those little beauties with bits of lime zest peeking out from amongst the snowy sugar coating. This Key Lime Cookies recipe produces such light, tender, and delicious cookies that they will disappear before you know it.
And don't think these lime cookies are just for summer! They're a fantastic addition to cookie tins at Christmas too. And always a welcome change from all the seasonal chocolate and peppermint. And who wouldn't want to dream of warm, sunny weather in the middle of winter?! Enjoy!
More Key Lime Recipes
Chocolate Covered Key Lime Bites are like bite-sized pieces of key lime pie covered in rich chocolate. Perfect for a summer treat.
Key Lime Brownies are fudgy brownies swirled with moist key lime cheesecake filling then topped with cream cheese frosting. A definite must for all brownie and cheesecake fans!
Key Lime Pie Popsicles from Easy & Delish are fun to make healthy and delicious popsicles that taste like key lime pie on a stick.
Key Lime Pudding Cake is a creamy, sweet dessert that magically bakes into two separate layers, a light airy sponge cake on top and a tangy custardy pudding underneath.
Find lots of easy cookie recipes here on 2CM!
Key Lime Cookies
Ingredients
- ¾ cup butter, room temperature
- 1 cup granulated sugar
- 2 cups powdered sugar, divided
- 2 eggs
- 1 ½ teaspoons vanilla extract
- 2 ⅝ cups all-purpose flour (2-½ cups + 2 Tablespoons)
- ⅜ cup cornstarch (¼ cup + 2 Tablespoons)
- 1 Tablespoon baking powder
- ¼ teaspoon salt
- ¼ cup key lime juice (I used Nellie & Joe's Key West Lime Juice)
- 6 teaspoons lime zest, finely grated, divided
Instructions
- Preheat oven to 325 degrees. Line 3 large baking sheets with parchment paper.
- In a large bowl of your electric mixer, beat butter with granulated sugar and 1 cup powdered sugar until light and fluffy.
- Continue to beat while adding eggs and extracts.
- In a medium bowl, combine flour, cornstarch, baking powder and salt.
- Add to the butter-sugar mixture, alternately with key lime juice and 4 teaspoons of zest, at low speed until well mixed.
- Using a tablespoon or a small cookie scoop, place cookie balls 1" apart on prepared baking sheets.
- Bake for 16 minutes or until the bottoms are just starting to turn a light brown. DO NOT OVERBAKE!
- While cookies are baking, mix 1 cup powdered sugar with the remaining 2 teaspoons lime zest in a large gallon-sized plastic bag. Rub the two together to impart some of the key lime flavor to the sugar.
- Remove cookies from the oven and let cool about 3-4 minutes on baking sheets. Remove carefully then place several at a time in the plastic bag containing powdered sugar mixture and gently toss. Shake excess off then place on wire racks and allow to cool completely.
- Store in airtight container.
Notes
- Add 4 teaspoons of basil to the cookie dough and cook as directed. The basil imparts a nice herbal flavor that complements the zesty key lime.
- Love chocolate? Go ahead and add ¾ cup of white chocolate chips to the batter. It makes these buttery cookies even more indulgent. Or just drizzle it on the top!
- Love even more lime flavor? Add a lime glaze by mixing ¾ cup powdered sugar with 3 Tablespoons of key lime juice. Drizzle on cooled cookies then sprinkle a little extra zest on top.
- Love any citrus-flavored cookies? Try this same recipe replacing the lime juice and zest with either lemons or oranges.
Nutrition
This post has been updated with step-by-step instructions and new photos. It was first published on August 18, 2015.
Yummy Cookies... Just can feel the taste in my mouth...
I would not be able to stop eating after just one of these little beauties! Your cookie tin is perfect for picnic-packing too.
These sound so good and I think adding basil would be an interesting but tasty choice!
Thanks Hezzid! The basil imparted a very nice but subtle taste. I think you could even add more for a more pronounced flavor.
Key Lime anything is good for me, but cookies? Oh I Love lime flavored cookies in summer or winter or anytime.
Me too! And I'm lucky enough to live in Florida and have key limes pretty much all year.
I love lime, and it sounds so refreshing! I'll have one with a margarita!!
I'm with you! If I was nearby I would come and join you and bring the cookies. 🙂
These look wonderful! I especially love the variations you tried! And you are right, they are the perfect end to a summer picnic.
Thanks Laura! I love them because they are so light that I can even eat them after I stuff myself with all the picnic goodies. lol
These look like they would melt in my mouth, Linda. I love key lime anything but especially cookies.
Stacy, key limes are one of my favorites too! I'll eat anything with that tart key lime flavor.
I love lime! Powdered sugar, dear me. I am going to have to give these a try!
If you love lime, you'll love these Terri! Hope you get to make them soon.
I love key lime and I love cookies covered with powdered sugar, so these definitely look like a win for me!
(The only problem is, it's much harder to sneak powdered sugar-covered cookies without people seeing the evidence... hmm.)
lol You are so right Jennifer! I guess we could always plead the 5th!
Oh, you got me, these sound fabulous!! What fun for a summer day!!
All the fun with eating these cookies is getting the powdered sugar all over. At least it is for me.
Me too! I love the fun of powdered sugar and they add just enough sweetness to these cookies to make them irresistible!