Black bean fajita

Name: Black bean fajita
Cuisine: American, Mexican, Latin American, TexMex
Ingredients: 400g can black beans, drained; small bunch coriander, finely chopped; 4 large or 8-12 small flour tortillas; 1 avocado, sliced, or 1 small tub guacamole; 4 tsp soured cream or crème fraîche; 1 red and 1 yellow pepper, cut into strips; 1 tbsp oil; 1 red onion, cut into thin wedges; 1 garlic clove, crushed; ½ tsp chilli powder; ½ tsp smoked paprika; ½ tsp ground cumin; 1 lime, juiced; 100g cheddar cheese