In a large, heavy skillet cook turkey in oil (or you can use vegetable cooking spray) about 5 minutes or until lightly browned,stirring to break up the meat. Add onions, tomato sauce, beef broth, sage, salt, garlic, and peppers. Bring to a boil, and reduce heat and cover. Simmer for 15 minutes, stirring occasionally. Meanwhile, mix the cornmeal, flour, baking powder, salt, rosemary, egg, milk and oil. Mix well and drop by tablespoons on top of the turkey mix. Cover and simmer 10 minutes or until dumplings are firm.