Combine The Dry Ingredients. In a small mixing bowl, combine gluten-free flour blend, cornstarch, baking soda, and salt. Whisk to combine and set aside.

Cream Butter, Sugars & Peanut Butter. In a large bowl or stand mixer, combine softened butter, brown sugar, sugar, and peanut butter. Cream 2-3 minutes, or until smooth and light.

Add Egg & Vanilla. Then, add the egg and vanilla extract and mix until just combined.

Add Dry Ingredients. Next, add the dry ingredients mixture to the mixer and stir until just until combined. (Try not to overmix!)

Chill The Dough. Cover the dough and chill at least 1 hour, up to 1 day before baking.

Preheat The Oven & Prep Your Station. When you're ready to bake, preheat the oven to 350 degrees F. Line two baking sheets with parchment paper and set aside. Add 1/2 cup of sugar to a shallow bowl to use for rolling the cookies before baking.

Chill The Hershey's Kisses (If You Remember). If you remember, pop the kiss candies in the freezer for a few minutes while you mix up the cookies. (This helps them not melt as much when you add them to the cookies so they set up faster, but it's not strictly necessary.)

Scoop, Roll & Bake. Use a small cookie scoop to spoon 1-tablespoon balls of dough. Smooth them into balls with your hands, then roll in sugar. Bake 8 cookies at a time per baking sheet, alternating between baking sheets in between batches so you don't put cool dough on a hot baking sheet. Bake cookies for 8-10 minutes, or until they no longer look wet and shiny. Pull out 8 chilled kisses just before the cookies are done.

Remove & Add Kisses. Immediately remove the cookies from the oven and add a Hershey's kiss to the center of each cookie, pressing down until the cookie looks crackled and the kiss is near the bottom of the cookie (don't push it all the way through, but press it in deep enough that it'll stick). Transfer the cookies to a wire rack to finish cooling completely. (Speed this up and help protect the chocolate by popping the rack in the refrigerator or freezer for a few minutes!) Repeat with remaining dough until all cookies are baked.