In the bowl of a stand mixer, cream butter and sugar on medium speed until light and flight, about 1-2 minutes.

Add vanilla, flour, cocoa powder, salt, and red velvet emulsion. Mix until all ingredients are incorporated and dough forms.

Turn dough out onto a sheet of plastic wrap or a lightly floured surface. Roll dough into a 10-inch log. Wrap in plastic wrap and chill in the fridge for at least 30 minutes to 1 hour.

Preheat oven to 350ºF and line two baking sheets with parchment paper.

Unwrap the cookie dough log and slice off the ends. Cut the log in half, and then cut each half in half to create four equal quarters. Pour sprinkles of choice into bowls and roll each quarter of dough in sprinkles, pressing into the dough if necessary.

Once coated in sprinkles, cut each quarter of dough into 5 to 6 slices. Arrange slices in four rows of three on each baking sheet. Baking each sheet tray for 12 to 15 minutes. Remove from oven and allow cookies to cool completely.

Store cookies in an airtight container at room temperature.