- Preheat your oven to 350°F.

- Line two baking sheets with parchment paper and set them aside.

- In a medium-sized bowl, sift together the flour, baking soda, and salt. Set this mixture aside.

- In a mixer bowl fitted with the paddle attachment, cream the butter, granulated sugar, and powdered sugar on medium-low speed for about 4 minutes.

- Add the egg and vanilla extract, mixing until just combined.

- Gradually add the dry ingredients to the wet mixture, mixing until just combined. Be careful not to overmix.

- Fold in the sprinkles.

- Shape the dough into balls, each about 1.5 tablespoons in size. An ice cream scoop can be useful for this.

- Place the dough balls on the prepared baking sheets, spacing them about 2 inches apart.

- Bake the cookies for 11-12 minutes, until the edges just begin to brown while the centers remain soft. Avoid overbaking.

- Let the cookies cool on the baking sheet for 5-10 minutes before transferring them to a wire rack to cool completely.