Sausage and ricotta pasta bake

Name: Sausage and ricotta pasta bake
Ingredients: 2 tsp vegetable oil; 2 red onions, peeled, sliced; 1 red chilli, finely chopped; 2 garlic cloves, sliced; 200g/7oz good-quality herb sausages, grilled until completely cooked through, cooled, thickly sliced; 350g/12oz penne, cooked according to packet instructions, drained; 200g/7oz ricotta; 2 ripe tomatoes, finely chopped; 100g/3½oz parmesan shavings, plus extra to serve; 1 tbsp chopped fresh parsley; 1 ready-made garlic baguette, sliced