1. Place tortillas onto workspace. Sprinkle 1/4 cup cheese over each tortilla.
2. Dividing each ingredient into 4 parts, continue layering on each tortilla in this order: black beans, onions, cilantro, tomatoes, pepper, and chicken. Top each with 1/4 cup cheese.
3. Squeeze lime juice over all. Cover with remaining tortillas.
4. Heat large skillet on med-high heat. Place 2 tortilla stacks in hot skillet and cook 3-5 minutes, or until tortilla is browned.
5. Carefully flip onto other side and cook until cheese is melted.
Serve with sour cream on the side.