Key Lime Thumbprint Cookies

Prep Time 25 minutes
Total Time 25 minutes
Servings 32 cookies
Author Sam Merritt



  • 1 cup unsalted sweet cream butter softened, 2 sticks
  • 2/3 cup light brown sugar packed
  • 1 tsp vanilla extract
  • 1 large egg yolk lightly beaten
  • 2 1/4 cup all-purpose flour
  • 1/2 tsp salt

Key Lime Filling

  • 1 cup premium white chocolate chips
  • 1/2 cup sweetened condensed milk
  • 3 Tbsp key lime juice
  • 1 tsp lime zest optional (key limes are expensive, I just used zest from a regular lime)


  • In KitchenAid or with hand mixer beat butter until creamed.
  • Add brown sugar and beat until light and fluffy.
  • Stir in vanilla and egg yolk, pausing to scrape down the sides and mixing until ingredients are well-combined.
  • Add flour, gradually (about 1/2 cup at a time), pausing to scrape down sides of bowl. Halfway through the addition of the flour, sprinkle in the salt with the beater still running.
  • Chill dough for 30 minutes.
  • Preheat oven to 350F and line cookie sheets with parchment paper (if using. An ungreased, non-stick cookie sheet will also work).
  • Roll cookie dough into approximately 1" balls and use thumb to create indent/crater in the center. Space cookies at least 1" apart.
  • Bake cookies for 10-12 minutes and allow to cool completely on pan.

Key Lime Filling (do not make filling until the cookies are cooled, if allowed to sit too long the filling will begin to harden so you want to make sure all of the cookies are ready before proceeding).

  • In small saucepan over medium-low heat, combine white chocolate chips and condensed milk.
  • Stir frequently until chocolate is melted and ingredients are well-combined.
  • Add Key Lime juice and lime zest and use a whisk to combine (the juice will take a little coaxing and stirring before it is well-combined with the condensed milk and chocolate chips, just keep whisking until the juice is no longer separated).
  • Reduce heat to low and spoon filling into thumbprints of cookies. Allow to cool completely before serving (filling may still be a little tacky to touch, even when cooled completely. This is normal).