To make Mario Batali's highly rated recipe for Roman-style tripe stew, simmer the tripe until very tender before slicing, sauteing and simmering it in tomato sauce. Batali's recipe provides additional directions for a basic tomato sauce, but any tomato sauce may be used.
Combine 2 pounds of tripe, 1/2 cup of white vinegar and 1 teaspoon of vanilla extract in a large pot. Add enough water to cover the tripe by 2 inches and bring to a boil. Once the mixture is boiling, reduce the heat and simmer for approximately 1 hour. Replenish the water as necessary, and simmer longer if the tripe is not tender after 1 hour.
Drain the tripe and allow it to cool. Slice the cooled tripe into 1-inch strips. Slice 1 red onion into thin slices and coarsely chop 4 cloves of garlic. Heat 2 tablespoons of extra virgin olive oil in a 14 or 16 inch skillet until almost smoking, then add the onions, garlic and tripe and saute for 3 minutes.
Add 2 cups of tomato sauce to the skillet and bring the mixture to a boil. Reduce the heat and cover the skillet, simmering the mixture for 30 minutes. While the tripe stew simmers, combine 1/4 cup of grated Pecorino Romano cheese, 1/3 cup of grated Parmigiano-Reggiano cheese and 1 finely chopped bunch of mint leaves in a small bowl. Stir the cheese and mint mixture to combine evenly.
Serve the finished tripe stew in warmed bowls and top with the cheese and mint mixture. This recipe makes six servings.