Stuffed Guinea Squash (Eggplant)

Preheat oven to 375 degrees F (190 degrees C).
Cut eggplant in half lengthwise. Carefully scoop out and chop flesh, leaving skin intact. Place in a shallow baking dish, and set aside.
Heat butter in a large skillet over medium high heat. Cook and stir eggplant, mushrooms, and onion until tender, 7 to 10 minutes. Stir in bread crumbs and 1 cup of Cheddar cheese. Fill eggplant shells with stuffing, and sprinkle with remaining cup of Cheddar cheese.
Bake in the preheated oven for 15 to 20 minutes, or until warmed throughout and melted on top.