Add a teaspoon of olive oil to a nonstick pan over medium heat. Add in the onion and sauté until softened, about 5 minutes. Then add in the bell pepper and continue to stir for an additional minute. Remove the vegetables to a bowl and set aside.
Add an additional teaspoon of oil to the pan, season the chicken breasts with salt and pepper, then sear them on each side until golden brown, about 3 minutes per side.
Add in the salsa and cumin, cover the chicken with a lid and allow to simmer over medium heat for 20 minutes, or until it shreds easily with two forks.
Meanwhile, heat a large nonstick skillet over medium high heat. Toast the Flatout breads on each side until slightly charred. Set aside.
Once the chicken is cooked through and tender, shred it in the sauce using two forks then add in the black beans, corn, onions and peppers. Stir to coat in the sauce.
Lightly grease a 15 x 10 inch casserole dish with a touch of olive oil.
Using a slotted spoon to avoid getting too much of the sauce, divide the filling mixture down the centre of 8 toasted Flatout breads (opened up landscape-wise like a book) and tightly wrap them. Place the enchiladas seal down in the casserole dish. Bake for 7 minutes.
Remove the dish and top the enchiladas with 1/2 cup of the enchilada sauce and the cheese. Bake for an additional 5-7 minutes, or until the cheese gets bubbly and melts.
Serve with additional enchilada sauce and garnish with fresh cilantro.