Preheat oven to 350 degrees F.
Pour half the of the enchilada sauce into the bottom of a baking dish.
Warm tortillas by wrapping in a damp paper towel and heating in microwave for 45 seconds or until soft and pliable.
Place 2 tablespoons of black been burger mixture onto the bottom third of a tortilla. Roll the tortilla up and place seam side down into the baking dish. Repeat with remaining Black Bean Burger mixture and tortillas. Pour the remaining enchilada sauce over the filled tortillas. Top with the Cheddar and bake in the preheated oven for 15 to 20 minutes or until the cheese is browned and bubbly.
Heat a grill or grill pan over medium-low heat.
In a food processor, pulse onion and garlic until finely chopped. Add 1 can black beans, cilantro, parsley, egg, and red pepper flakes and pulse to combine.
Transfer mixture to a large mixing bowl, add the remaining can of black beans and the bread crumbs. Season with salt and pepper, to taste, and mix until well combined.
Reserve 1/3 of the black bean mixture for Black Bean Enchiladas. Divide remaining mixture into 4 portions and form into patties. Place on hot oiled grill over medium-low heat and cook about 6 minutes a side or until heated through. Toast hamburger buns on a grill. Place a burger on the bottom of each bun. Top with lettuce, tomato and ketchup. Cover the burgers with the top of the bun and serve.