In a medium bowl, combine the rinsed black beans, salsa, chili powder, and cumin. Mash about half of the beans lightly with a fork to create a thicker filling consistency.
Heat a large non-stick skillet or griddle over medium heat.
Place one tortilla in the hot skillet. Sprinkle half of the tortilla surface with about 2 tablespoons of the vegan cheese.
Spoon about 1/4 cup of the black bean mixture over the cheese. Sprinkle with a little more cheese if desired.
Fold the empty half of the tortilla over the filling to create a half-moon shape.
Cook for 2 to 3 minutes per side, pressing down gently with a spatula, until the tortilla is golden brown and the cheese inside is melted.
Remove from the skillet and keep warm while you cook the remaining quesadillas. Add a small amount of oil to the skillet between batches if needed for crispness.
Slice each quesadilla into wedges and serve immediately with your choice of toppings.
Notes
For a gluten-free option, substitute corn or gluten-free tortillas. Note that gluten-free tortillas may require slightly lower heat to prevent cracking.
You can prepare the black bean filling up to two days ahead and store it in the refrigerator.
If you do not have a vegan cheese substitute, you can use a thin layer of mashed avocado mixed with nutritional yeast for creaminess, though the texture will differ.