Polenta Pizza

Details

Ingredients

• 1 tablespoon olive oil
• 1 Spanish onion, thinly sliced
• 1 green bell pepper, thinly sliced
• 1 (3.5 ounce) link hot Italian sausage, sliced
• ¼ cup sliced fresh mushrooms, or more to taste
• 1 slice prepared polenta, cut into 4x4-inch piece
• ¼ cup spaghetti sauce, or as needed
• 1 ounce shredded mozzarella cheese