Preheat oven to 400 degrees. Line a baking pan with foil, and spray with cooking spray. (Or use a silpat mat, or parchment paper.)
Mix flour, baking powder and soda, salt and spices together and set aside. In another bowl, mix together the mashed sweet potato with the other wet ingredients. Combine the wet and dry ingredients, mixing until everything is just combined.
The dough will be slightly sticky, so I sprayed the inside of an ice cream scoop with cooking spray and dropped it onto the baking pan. However, you can also use a spoon or measuring cup to make 'drop biscuits' onto the pan.
Bake for 12-15 minutes, or until golden brown. Enjoy warm or at room temperature.