Preheat the oven to 180°C.
Cut the tomatoes in half and arrange them in a large baking tray.
Roughly chop the celery and carrot. Peel and cut the onion into thin wedges. Peel the sweet potato then dice into 3 cm chunks. Tuck the chopped veggies and the peeled garlic cloves between the tomatoes. Drizzle the oil and scatter the oregano and chilli all over them. Season with salt and pepper, then combine well.
Bake for 25-30 minutes, or until the vegetables have softened.
Transfer the roasted vegetables to a saucepan, including the cooking jus. Add the stock and bring to the boil. Turn off the heat, add the fresh herbs and the vinegar.
Using a hand-held blender, whiz the soup until you get a smooth, creamy texture. Add more stock if it’s too thick. Keep it warm under a lid.
Boil some water in another saucepan and cook the ravioli according to the packet’s instructions. This should take a couple of minutes. Drain, then transfer them straight to serving bowls. Ladle some tomato sauce over them and serve with plenty of ground pepper and some basil leaves or wild rocket leaves.