Preheat the oven to 450 degrees and grease an 8-inch round cake pan with butter.

Whisk together the flour, brown sugar, baking powder, salt and baking soda.

Cut in the butter with a pastry blender until the mixture resembles coarse sand.

In a separate bowl, stir together the mashed sweet potatoes and milk.

Pour the sweet potato mixture into the bowl with the dry ingredients and stir until the dough begins to come together. If the dough is too sticky, add more flour one tablespoon at a time.

Transfer the dough to a lightly floured surface and roll out until it’s around one inch thick. Use a 2-inch round cookie cutter to cut out the biscuits, then gather up the scraps and re-roll the dough. Cut the remaining dough into rounds.

Arrange the biscuits in the prepared cake pan and bake for 16 to 20 minutes.