Cook first 3 ingredients in a large skillet over medium heat until sausage is browned and vegetables are tender, stirring until sausage crumbles. Drain.
Combine sausage mixture, cornbread crumbs, and remaining ingredients, stirring well. Spoon mixture into a greased 13" x 9" x 2" baking dish.
Bake, uncovered, at 350° for 35 to 40 minutes or until lightly browned and thoroughly heated.