Preheat the oven to 180°C.
Cut the sweet potatoes, tomatoes and onion in half (unpeeled) and place them in a baking tray. Tuck the garlic cloves (and chilli, if used)between them then drizzle with oil and toss well.
Bake for about 25 minutes until the vegetable have softened.
Let them cool for 5 minutes, then remove all skins (and seeds of chilli).
Put the vegetable flesh in a saucepan including any cooking jus. Add enough water to cover them together with the stock pot.
Bring to the boil, cook for 5 minutes then add a handful of fresh herbs of your choice. Turn off the heat.
Using a stick blender, process the soup until creamy.
Add more water/stock if it’s too thick, then add the peas and bring to the boil again. Cook for two minutes, then serve.