Heat the olive oil in a large pot over medium-high heat. Add the onion, garlic, oregano and chipotles in adobo (chillies and sauce) and cook for 2 minutes while stirring.
Add tomato, stock and salt and bring to a simmer. Cook for 3 minutes, then blitz until smooth using a stick blender.
Add potato and corn to the sauce and simmer for 10 minutes.
Stir in the black beans.
Place the fish pieces on top of the sauce. Don’t stir them in. Return the sauce to a simmer, cover with a lid and cook for 5 minutes.
Once the fish is cooked (check to see that it flakes), add the coriander and lime juice.
Gently push the fish under the sauce, then ladle into bowls, garnished with extra coriander leaves. Serve extra lime wedges alongside.
