Steak and Mushroom Casserole

2 pounds sirloin steak
1/3 cup flour
1 teaspoon salt
1/4 teaspoon pepper
1 tablespoon dry mustard
2 tablespoons olive oil
2 1/2 cups sliced mushrooms
1 medium onion, sliced
2 tablespoons red wine
3 tablespoons brown sugar
1 1/2 tablespoons Worchestershire sauce
1 can (19 oz.) tomatoes

Cut beef into bite sized cubes. Combine flour, salt, pepper, and dry mustard. Toss beef cubes in the flour mixture to coat.

Heat oil in a large frying pan, and brown beef cubes on all sides. Brown in batches and remove as done. Add more oil if necessary.

Place the browned beef cubes in a large casserole dish. Add the remaining ingredients. Cover and bake at 350 degrees F. for 1 and 1/2 to 2 hours, until tender. Stir occasionally. Makes 6 servings.