1. First, start by preheating the oven to 350°F
2. Line a baking sheet with parchment paper and set aside.
3. Cream the butter, granulated sugar, and brown sugar until light and fluffy, about 3 minutes. Add in the egg yolks, and the vanilla and mix again until fluffy and well incorporated.
4. Add in the flour, cocoa powder, baking soda, and salt and mix just until combined. Don't over mix.
5. Using a small cookie scooper, scoop out 28 equal cookie dough balls.
6. Roll them between the palm of your hand then roll one side in the sprinkles.
7. Set on the prepared baking sheet.
8. Repeat with the rest of the cookies and bake for 10 minutes in the preheated oven.
9. Pull out the baked cookies, let them cool on the baking sheet for 5 minutes then transfer to a cooling rack.
10. Enjoy with a tall cup of cold milk.

Recipe Notes: We made these for Valentine's Day, but the opportunities are endless! Make these for a birthday party, gender reveal, the holidays and more! Just change the color of sprinkles. Cookies can be stored in an airtight container at room temperature for up to 5 days.