I found this recipe on Pinterest. The link sent me to Heather Christo's website.
Serves 8
6lbs Whole tomatoes
8 Cloves of garlic - skin on
1/2C Olive oil
4T Butter
2 Large yellow onions
Large handful fresh basil
4C Good vegetable stock
1C Heavy cream
Kosher salt
Preheat oven to 204C
Arrange tomatoes and garlic on a baking sheet and drizzle with the olive oil, sprinkle with salt. Roast for 30 mins.
On the stove, in a large soup pot, melt the butter and fry onions on low for 30 mins.
Remove tomatoes from oven. Squeeze garlic from the skins into the soup pot add the tomatoes and oil from the baking sheet as well. Add basil and stock. Turn up the heat and cook it for 15 mins.
Remove from the heat and puree. Stir in the cream with a spoon. Season to taste.
Notes
I think the cream is optional here. The soup tastes so delicious I am not certain the cream really adds that much to it. So leave it out if you want.
I also think that this method of roasting the tomatoes could be used on many other vegetables and you could make a lovely roast vegetable soup that way.