Cut tomatoes in half and place in roasting tin.
Peel the garlic and also place it in roasting tin.
Season the tomatoes and garlic with some salt and drizzle with olive oil.
Place in oven to roast at 220 for 40 minutes. Flipping the ingredients half way through.
Cut your onions thin, I like to use IKEAS mandoline to get an even round cuts, and then cut them in half to make them into slivers.
Add some olive oil into a frying pan and add onions.
Cook for 20 minutes stirring occasionally until they caramelize.
Using a food processor or an Immersion Hand Blender, puree the roasted tomatoes and carmalized onions.
Add fresh basil leaves and puree as well.
Return ingredients to pot and add vegetable stock.
Bring to boil and serve.
For a smooth soup run it through a sieve.
You can serve with toasted bread slices or you can add a dash of cream.