Pasta bake with eggplant and fennel

Ingredients

• 2 to 3 hot Italian sausages
• 1 tsp vegetable oil
• 1 onion , chopped
• 4 garlic cloves , minced
• 1 small eggplant , peeled and cut into 1/2-in. cubes
• 1 tbsp granulated sugar
• 1 small fennel bulb , or 2 celery stalks, sliced
• 1 red bell pepper , chopped
• 796-mL can diced tomatoes
• 1 cup chicken broth , or bouillon
• 1/4 cup chopped fresh basil , or 1 tsp dried basil
• 1 tsp hot-red-chili-flakes , optional
• 1/2 tsp dried oregano leaves
• 1/2 tsp salt
• 1 1/2 cups small uncooked pasta , such as macaroni
• 1/2 cup grated parmesan , or crumbled feta