Preheat oven to 350F. Line baking sheet with cookie sheet and set aside.
In a stand mixer fitted with a paddle attachment cream butter, coconut sugar and butter flavoring until light and fluffy. Add egg yolks, one at a time, beating after each addition until fully incorporated.
Add remaining ingredients and mix on lowest speed until a thick dough forms.
Place tablespoon sized balls of dough on baking sheet, then press each one down slightly until it resembles a small cylinder.
Bake cookies for 5 minutes, then remove from oven and lightly press each cookie down with the back of a fork. Return to oven and finish baking for an additional 5 minutes.
Remove cookies from oven and allow to rest on cookie sheet a few minutes before transferring to cooling rack to cool completely.