Add the sausage to a large skillet, and cook over medium heat. Break the sausage up as it cooks, stirring occasionally.
Once completely browned, strain the sausage to remove any excess fat or grease and return the sausage to the skillet.
While the sausage cooks, prep the zucchini. Cut the ends off, and then halve the zucchini lengthwise.
Cut the zucchini again cross wise to create 1/4" pieces, and add them to the skillet.
Stir them into the sausage until evenly incorporated, cover the skillet, and let the mixture cook over medium heat for 2 minutes.
In a mixing bowl, whisk together the condensed soup, sour cream, garlic powder, and thyme. Pour this mixture into the sausage, stirring to evenly combine.
In a separate mixing bowl, add the stuffing mix & the broth. Stir them together, and let sit just long enough to moisten the stuffing.
Lightly spray a 3 quart casserole dish with non stick cooking spray, and scoop half of the stuffing mix into it. Gently spread it out as evenly as possible.
Pour the sausage mixture out into the casserole dish, gently spreading out. Top evenly with the remaining stuffing.
Drizzle the melted butter evenly out over top of the casserole.
Cover the casserole dish tightly with aluminum foil, and bake at 350 degrees for 15 minutes. Carefully remove the foil, and bake for an additional 20 minutes- until the casserole is bubbly and the stuffing topping is golden brown.
We often serve this recipe as is, but if you want to to flesh it out into a complete meal- serve it with white rice & a simple side salad. Maybe even a slice of crusty bread too, for mopping up any juices.