Preheat oven to 425°F.
Spread tomatoes, onions and garlic cloves on a baking sheet. Drizzle with olive oil. Season with salt and pepper. Bake for 30-35 minutes.
Assemble grilled cheese with cheese and French shallot confit.
In a frying pan, over medium heat, add a spoonful of butter. Add the grilled cheese and cover. Cook for 2-3 minutes on each side.
Place tomatoes, onions and garlic cloves in a blender. Add cream and basil leaves. Mix well. Add a little broth for a thinner soup.
Serve the grilled cheese with the soup.