Heat oil in a large frying pan over medium heat. Once hot, add the vegetables to the pan with seasonings and cook, stirring frequently until they become soft.
While the vegetables cook, mix all the ingredients for the enchilada sauce into a small sauce pan over medium heat and whisk together.
Bring to a boil then take off the heat.
Once the vegetables are cooked to your liking, drain and rinse the black beans and add them to the filling. Once the beans are heated through you are ready to assemble the enchiladas.
Add 1/3 of the enchilada sauce to the bottom of a 9x13 baking dish.
Make the enchiladas one at a time by placing a tortilla in the dish, adding a scoop of filling, then rolling up the tortilla.
Repeat until all the tortillas are filled. Pour the remaining sauce over the enchilada then spread the sauce with a spatula to make sure they are completely covered.
If desired, top with shredded cheese. Bake at 350° F for 20 minutes or until cheese begins to bubble.
serve your black bean fajita enchiladas topped with avocado, sour cream, or your favorite taco toppings.