Vegetarian Potato and Squash Casserole

Ingredients (8)

• ✓ cooking spray
• ✓ 2 baking potatoes, cut into1/2-inch slices
• + salt and ground black pepper to taste add to pantry
• ✓ salt and ground black pepper to taste
• + 3 large yellow summer squash, cut into 1/2-inch slices add to pantry
• + 4 large tomatoes, cut into 1/2-inch slices add to pantry
• + 1 sweet onion, cut into 1/4-inch slices add to pantry
• + 2 tablespoons butter add to pantry