First make the sauce. Preheat the oven to 180°C.
Cut the tomatoes in half and the pepper into 4 pieces. Put them in a large baking tray.
Cut the onion into 4 wedges and tuck them between the tomatoes together with the garlic (you don’t need to peel them). Add the herbs, oil and chilli (if used). Season with salt and pepper, then toss.
Put the tray in the oven and bake for 25-30 minutes until the vegetables are soft and a little charred.
Take the tray out of the oven and let it cool a bit.
Remove the skin of all vegetables. (Scrape out the chili seeds if you don't want the sauce to become too spicy!) Put their flesh into a saucepan, then using a hand-held blender, process into a thick, smooth sauce.
Boil some water in another pan and blanch the asparagus for two minutes and set aside in cold water. Keep the water boiling in the pan add the gnocchi in batches. When they float to the surface of the water, transfer them with a slotted spoon to a mixing bowl.
Warm up the red pepper sauce, then mix with the drained gnocchi.
Drain the asparagus tips and add to the gnocchi.
Serve immediately.