Preheat the oven to 400 degrees F. Toss together the tomatoes, ¼ cup olive oil, salt, and pepper. Spread the tomatoes in 1 layer on a baking sheet and roast for 45 minutes.
In an 8-quart stockpot over medium heat, saute the onions and garlic with 2 tablespoons of olive oil, butter, and red pepper flakes for 10 minutes, until the onions start to brown.
Add the canned tomatoes, basil, thyme, chicken flavor bouillon, sugar, and water. Add the oven-roasted tomatoes, including the liquid, to the baking sheet. Bring to a boil and simmer uncovered for 40 minutes.
Using a hand-held immersion blender, purée the soup until smooth or desired consistency.*(Alternatively, let the soup cool slightly and purée in batches in a blender.
Be sure to crack the lid or remove the center cap to allow steam to escape.) Taste for seasoning. Ladle the tomato soup into bowls and garnish with fresh basil and croutons, if desired. Enjoy!