Preheat oven to 425F. In a large bowl, toss tomatoes, onions, red pepper, and garlic cloves with olive oil, salt, black pepper, red pepper flakes, and thyme. Arrange tomato mixture on a sheet pan and roast for 25 minutes. Transfer roasted vegetables, inclcuding any juices from the pan, to an 8 quart pot. Add the French bread and chicken stock. Bring to a simmer and cook for 20 minutes. The French bread wiill thicken and add body to the soup. Puree the soup and serve with croutons, a little olive oil, a spoon of goat cheese, and fresh basil (or use it to dip your favorite grilled cheese sandwich in!).