Carne Guisada

Ingredients

• 2 tablespoons vegetable oil
• 2 pounds sirloin tips, trimmed of all fat and gristle and cut into 1/2-inch cubes
• 1 cup green bell pepper, chopped
• 1 cup chopped onions
• 1 pound small red potatoes,peeled and cut into 1/2-inch cubes
• 4 garlic cloves, minced
• 1 serrano chile, minced
• 1/2 cup chopped tomatoes
• 1/2 teaspoon salt
• 1 teaspoon pepper
• 1/2 teaspoon ground cumin
• 1/2 cup tomato sauce
• 1 tablespoon flour