Preheat the oven to 375°F (190°C). In a medium-sized mixing bowl, thoroughly stir together the all-purpose flour, baking soda, and baking powder. Set the dry mixture aside.
Place the softened butter and granulated sugar in a large mixing bowl. Using either a hand mixer or stand mixer, beat them together until the consistency becomes creamy and smooth.
Add the egg and vanilla extract, then continue beating until both are completely incorporated into the butter mixture.
Gradually add the reserved flour mixture to the butter and sugar mixture, beating as you go until a dough develops.
The mixture may initially look somewhat crumbly. Continue mixing until the dough holds together and forms a cohesive mass.
Portion the dough with a 1-inch cookie scoop, then roll each portion between your hands to create a round ball.
Arrange the dough balls on a greased baking sheet. Press each one with the smooth bottom of a drinking glass until the dough is approximately ½ inch thick.
Pour the sprinkles into a small bowl. Gently press the top of each flattened dough round into the sprinkles so the surface is evenly covered.
Place the decorated dough back onto the baking sheet with the sprinkle-coated side facing upward.
Bake in the preheated oven for 8–10 minutes, or until the cookie edges are lightly golden.
Leave the freshly baked cookies on the baking sheet for approximately 3 minutes.
Transfer them to a wire cooling rack and allow them to cool completely before serving.