Key Lime Pie Cookies

A vanilla buttery white chocolate cookie, pressed with a divot while it's still warm, then filled with key lime buttercream and finished with fresh zest. Key lime pie you eat with one hand.

Makes: 8 large cookies · Active: 20 minutes · Chill: 2 hours minimum · Bake: 15–18 min at 350°F

Ingredients

The Cookie

• 8 oz unsalted butter (2 sticks), softened
• ¾ cup brown sugar
• ¼ cup white sugar
• 1 egg
• 1 tsp vanilla extract
• 1½ cups all-purpose flour
• ½ tsp baking powder
• ½ tsp baking soda
• ½ tsp sea salt
• 1 cup white chocolate chips

Key Lime Frosting

• 4 oz unsalted butter (1 stick), softened
• 2 cups powdered sugar
• 8–10 key limes — for zest and juice

Make the cookies

1. Soften the butter, then beat it with both sugars until the mixture is smooth and lightened (about 4 minutes).
2. Add the egg and vanilla extract. Mix again until smooth and fluffy.
3. Add the flour, baking powder, baking soda, and sea salt. Mix until just blended (about 1 minute) — stop as soon as the flour disappears. Overmixing makes the cookie tough.
4. Fold in the white chocolate chips.
5. Form the dough into balls, 3.5 to 4 oz each. At 4 oz you'll get about 8 cookies.
6. Chill the dough in the refrigerator or freezer for at least 2 hours.

Bake

7. When you're ready to bake, preheat the oven to 350°F.
8. Bake for 15 to 18 minutes. Start checking at 15 — you want browned edges.
9. Let the cookies cool for 5 minutes, then use a cookie press or tablespoon to create a divot into the center of each one while they're still warm and pliable. The back of a rounded measuring spoon works well.

Wait here: Let the cookies cool completely before you frost them. Warm cookies will melt the buttercream straight out of the divot.

Key lime frosting

10. Let the butter come to room temperature.
11. Add 1 cup of the powdered sugar and mix until fully blended.
12. Zest 4 of the key limes finely into the frosting.
13. Squeeze the juice of those same 4 limes into the mix.
14. Add the second cup of powdered sugar and mix again.
15. Keep adding key lime juice, a little at a time, until you reach a smooth pipeable consistency and the lime flavor comes through clearly.
16. Spoon or pipe the frosting into the center of each cooled cookie, then grate fresh lime zest over the top.

Notes from the kitchen

• The chill is not optional. Two hours is the floor; overnight gives you a thicker cookie with a better chew.
• Key limes are small and give up their juice reluctantly. Buy all 10 — you'll want the margin when you're adjusting the frosting at the end.
• Roll the limes hard under your palm before cutting. You'll get noticeably more juice.
• Zest before you juice. It's nearly impossible the other way around.
• 3.5 oz dough balls give you 9 slightly smaller cookies if you'd rather stretch the batch.
• Store frosted cookies in a single layer in the refrigerator and bring them back to room temperature before serving. 
  

My Favorite Ingredients & Kitchen Tools

Find the cookie press here (it's actually an espresso tamper but it works beautifully for cookies): Stainless Steel Cookie Press