Combine all the ingredients for the dip in a mixing bowl. Keep refrigerated until ready to serve.
Preheat the oven to 400°F. Line a baking sheet with parchment paper.
In a mixing bowl, combine the mashed sweet potatoes, black beans, ground cumin, grated cheese, chili powder, cilantro, salt and pepper. Mix well. Taste and adjust the seasoning accordingly.
Place a 1tbsp of the mixture in the center of each empanada disc. Moisten the edges of the dough with water; fold over the filling. Press edges together to seal. Press the tines of a fork to make sure they are well closed.
Place the prepared empanada on the prepared baking sheet. Using a sharp knife and make slits on the top. Coat them evenly with cooking spray.
Bake for 15~18 minutes or until lightly browned on the top.