Preheat oven to 350 degrees fahrenheit and line a baking sheet with parchment paper or a silicone baking mat.

Melt the butter and mix with mashed yam, cinnamon and milk until combined. Slowly stir in flour until a dough is formed. Roll 1/4 inch thick and cut with cookie cutter.

Place on your prepared baking sheet and bake for 15 to 20 minutes or until edges start to brown.

Cool and refrigerate.