Preheat the oven to 200°F.
If using a frozen whole duck, thaw it in the refrigerator overnight. Remove the giblets and neck.
Place the duck breast side up on a wire rack over a rimmed baking sheet. This is to catch the fat that comes from the duck and allow it to not sit in the fat while cooking. Score the skin on top of the breast.
Bake for 5 hours at 200°F. Once finished, remove it from the oven and allow it to cool completely. While it is cooling you can boil, microwave, or bake a sweet potato if needed. Mash the cooked potato flesh.
Peel away the layer of skin and fat from the duck. Remove enough meat to make one cup.
Place the meat in a food processor and pulse until the meat is finely chopped.
Preheat oven to 350°F. Line a baking sheet with parchment paper.
Place the oats and flour in a bowl and stir or whisk to combine.
Place the sweet potato, melted coconut oil, egg, water, and duck meat in a bowl. Stir to combine.
Add the flour mixture to the wet ingredients mixture and combine until a dough forms.
Roll out the dough and cut shapes with your favorite cookie cutter. Re-roll and cut until all the dough is used up.
Place the cutouts on a baking sheet and bake at 350°F for 15-18 minutes.
Remove from oven and allow to cool to room temperature.
Store in an airtight container in the refrigerator.