Preheat the oven to 400F.
Poke the sweet potatoes all over with a fork and place on a foil lined baking sheet in the oven until fork tender, about 1 hour. Turn the oven down to 350F.
Remove from the oven, allow to cool slightly, then slice down the middle and scoop out all the pulp into a bowl.
To the sweet potato pulp, add the garlic powder, onion powder, cumin, salt, black beans, and 1 cup of cheese. Stir to thoroughly combine.
Pour half of the enchilada sauce into a 9x11 baking dish.
Place about 1/2 cup mixture into the middle of each tortilla and roll up.
Place the enchiladas, seam side down, into the baking dish. Pour the remaining enchilada sauce on top.
Cover with foil and bake for 15 minutes.
Remove foil and sprinkle with cheese and bake uncovered for an additional 15 minutes until cheese is melted and browned slightly
Note: The sweet potatoes can be baked up to 2 days ahead of time and the pulp removed and stored in the fridge.