01 - Preheat oven to 350°F. Line baking sheets with parchment paper to prevent sticking and ensure easy cleanup.
02 - In a large mixing bowl, beat softened butter and granulated sugar together using an electric mixer on medium-high speed until the mixture appears pale, light, and fluffy—approximately 3 to 4 minutes.
03 - Add the large egg and vanilla extract to the butter mixture. Beat on medium speed until fully combined and the batter appears smooth and glossy.
04 - In a separate medium bowl, whisk together the all-purpose flour, salt, and baking powder until evenly distributed.
05 - Gradually add the dry ingredient mixture to the wet batter while mixing on low speed. Continue mixing just until the flour disappears—avoid overmixing to prevent tough cookies.
06 - Sop approximately 1 tablespoon of dough and roll between palms to form smooth balls. Roll each ball generously in pastel sprinkles or colored sanding sugar to coat completely.
07 - Place coated dough balls 2 inches apart on the prepared baking sheets, allowing room for slight spreading during baking.
08 - Bake for 8 to 10 minutes. Cookies are done when edges appear set and lightly golden, but centers remain slightly soft to the touch.
09 - Remove baking sheets from oven immediately. Gently press one chocolate blossom kiss into the center of each warm cookie while the dough is still soft—the candy should sink slightly but remain visible.
10 - Allow cookies to rest on the baking sheet for 5 minutes to set. Using a spatula, transfer to a wire cooling rack and let cool completely before storing or serving.