Preheat oven to 350 degrees F.
In a large skillet, heat the olive oil over medium high heat. Once hot, add the onions and saute for 5-7 minutes until soft. Add the kale and cook down until wilted. Add the diced green chiles, cumin, garlic powder and red pepper flakes and stir to combine. Season with salt as needed.
Add the black beans into the mixture along with ½ cup of the enchilada sauce. Stir to combine and remove from heat.
To assemble the enchiladas, set up an assembly line including: tortillas, enchilada sauce, veggie mixture, mashed sweet potatoes, cheese and green onions. Lay out the tortillas on a flat surface and spoon 1 tablespoon of the mashed sweet potatoes in a line down the center of the tortilla. Add equal amounts of the veggie and onion mixture, pepper jack cheese, and 1 tablespoon of green onions each.
Pour another ½ cup of the enchilada sauce in the bottom of a 9x13 baking dish. Place the rolled up tortillas in the dish. Spread the remaining enchilada sauce on top of the tortillas, and sprinkle on the remaining shredded cheese.
Bake uncovered for 20-25 minutes. Remove from oven and serve immediately, garnished with the remaining green onions, cilantro and a drizzle of cumin crema.