Preheat oven to 350°F and line a baking sheet with parchment paper.
In a medium bowl, whisk together flour, protein powder, baking powder, baking soda, and salt.
In a separate bowl, beat butter, granulated sugar, and brown sugar until light and fluffy.
Mix in the egg, vanilla extract, and almond extract until smooth.
Add dry ingredients to wet and mix until just combined.
Fold in rainbow sprinkles.
Scoop 2–3 tablespoon-sized dough balls and roll in extra sprinkles.
Chill dough for 20 minutes. This step is key for thicker, bakery-style cookies.
Bake for 10–12 minutes, until edges are set and centers are soft.
Let cookies cool on the pan for 5 minutes before transferring.