Step 1

Preheat oven to 400 degrees. In a large skillet, heat oil over medium-high. Add mushrooms and cook, stirring often, until browned, 7 minutes. Add garlic and cayenne; season with salt and pepper. Add black beans and stir to combine. Cook until beans are warmed through, 2 minutes. Remove from heat.

Step 2

Arrange 5 tortilla halves in a 2-quart baking dish. Top with half the bean mixture and 1/2 cup salsa, then sprinkle with one-third the cheese. Repeat with another layer of tortilla halves, bean mixture, salsa, and cheese. Top with remaining tortilla halves, salsa, and cheese.

Step 3

Cover with foil and bake until center is hot and cheese melts, 10 minutes. Uncover and bake until cheese is bubbling, 5 minutes.