Preheat oven to 375℉.
Slice tomatoes lengthwise and lay them face up on a baking sheet. Add garlic cloves. Drizzle with olive oil and then sprinkle with salt and pepper.
Roast tomatoes for 1 hour. Remove from oven and set aside.
Heat 2 tbsp of olive oil in a large pot (or Dutch oven) over medium-high heat.
Add chopped onion and saute for about 5 minutes, or until onion is translucent.
Stir in Thyme, salt, and pepper. Saute for 1 minute.
Add can of crushed tomatoes, basil, and sugar to the pot. Lower heat and simmer for about 10 minutes.
Add the chicken stock and the roasted tomatoes and garlic to the pot and simmer for 30 minutes, stirring occasionally.
Remove the soup from heat. Using an immersion blender, puree the soup until smooth.
Stir in the cream.