Preheat oven to 400. Combine sausage, onions, garlic and oil in large heavy skillet or Dutch oven and sauté over medium high heat until sausages begin to brown. Break up sausages with back of spoon, cooking about 12 minutes. Remove from heat. Mix in crushed tomatoes, beans, parsley and oregano. Season to taste with salt and pepper. Spoon mixture into 8x8x2 glass baking dish. (Can use casserole dish instead)
Combine breadcrumbs and Parmesan cheese and sprinkle evenly over cassoulet. Bake until cassoulet is heated through, bubbling up around the edges and light brown on top, about 35 minutes.
You can add chunks of cooked duck breast, pork, ham slab bacon or any left over meat, before you bake it.