Start by preheating the oven to 350F, then line a large baking sheet with parchment paper and set aside.
In a stand mixer cream the butter, granulated sugar and brown sugar together using a paddle attachement until light in color and fluffy. Add in the egg white and the vanilla and mix again for 30 seconds or until fully incorporated.
½ cup butter, ½ cup granulated sugar, 3 tablespoon brown sugar, 1 large egg white, 1 teaspoon vanilla
Add in the flour, baking soda, baking powder, and salt and mix just until the flour disappears. Fold in the sprinkles then using a small cookie scooper (2tbsp), scoop out equally sized cookie dough balls, roll them in the sugar, and place them on the parchment-lined baking sheet. Make sure to leave 2 inches between each cookie because they will spread.
1 &½ cup all purpose flour, ½ teaspoon baking soda, ¼ teaspoon baking powder, ¼ teaspoon salt, ⅓ cup sprinkles
Bake the cookies for 8 minutes, pull them out and let them rest on the cookie sheet for 5-10 minutes then transfer to a cooling wrack. Enjoy immediately or store in an airtight container.