Cook the lima beans as directed; drain well and set aside.
In a large skillet over medium heat, cook the sausage with the chopped onion, carrots, and celery until the sausage is no longer pink. Add the tomatoes, herbs, and seasonings and cook until hot and bubbly. Add the drained baby lima beans and stir to combine.
Transfer the lima bean mixture to the prepared baking dish.
Cover the casserole tightly with foil or a lid and bake for 30 minutes. Uncover and continue baking for 15 minutes longer.