Step 1

In a medium bowl, whisk the flour, baking powder, and salt. Set aside.

Step 2

In a large bowl, using a hand mixer or a stand mixer fitted with a paddle attachment, beat the butter and granulated sugar together on medium-high speed until creamed, about 1 minute.

Step 3

Add the egg and vanilla to the butter mixture and beat on high speed until combined, about 1 minute.

Step 4

Scrape down the edges of the bowl with a spatula and beat the batter again, if needed to combine.

Step 5

Add the dry ingredients to the wet ingredients and mix on low until just combined.

Step 6

Fold the sprinkles into the dough. The dough will be thick and sticky.

Step 7

Scoop about 2 tablespoons of the dough at a time and roll the scooped portions into balls. If desired, lightly dip the tops of the balls in more of the sprinkles.

Step 8

Place the sprinkle-covered dough balls on a large plate.

Step 9

Cover and chill the sprinkle-covered dough balls in the refrigerator for at least 2 hours and up to 4 days.

Step 10

Preheat the oven to 350 degrees F.

Step 11

Line a baking sheet with parchment paper or a silicone baking mat.

Step 12

Arrange the chilled dough balls 3 inches apart on the prepared baking sheet.

Step 13

Bake the cookies until lightly brown on the sides and the centers still look very soft, for about 12-13 minutes.

Step 14

Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.

Step 15

Serve.