Trim the fat off the round steak and cut it into pieces.

Roll the steak pieces in flour, salt, and pepper to coat evenly.

Brown the floured steak pieces in cooking oil in a skillet.

Transfer the browned steak to a cooker (e.g., Dutch oven or slow cooker).

Alternate layers of steak, sliced onions, and chopped mango peppers in the cooker.

Pour the canned tomatoes over the steak and vegetable mixture.

Cook on medium heat (or low in a slow cooker) for about 1 hour, or until the steak is tender.

Stir the mixture often during cooking to prevent sticking.