1 lb. haddock or flounder
5-6 limes
1 red onion
Salt and pepper to taste
Cilantro leaves

Cut fish into square pieces and place in separate dish to marinate. Squeeze juice from limes into a mixing bowl. Cut onion and add to bowl. Add salt and pepper to taste. Sprinkle in cilantro leaves.

Pour marinade over fish and let marinate for a few hours before serving. (Overnight marinating is recommended.)