Preheat oven to 375. Cut plum tomatoes lengthwise and cut the onion into large chunks. Lay the tomatoes, onions, and 4 garlic cloves onto a large baking sheet lined with parchment or foil. Drizzle with 3 tablespoons of olive oil and season generously with salt and pepper. Roast for 50 min to 1 hour and allow to cool. Once the roasted tomato/onion/garlic mixture has cooled a bit, transfer it to a blender and puree until smooth. In a medium-sized pot over medium heat, add 1 T olive oil, 2 cloves minced garlic, red pepper flakes, salt, and pepper. Cook about 1-2 minutes until garlic is fragrant. Pour in the pureed tomato mixture and cook about 5 minutes. Then add the tomato paste, sugar, chopped basil, red wine, chicken stock and balsamic vinegar and stir to combine. Allow the mixture to come to a boil and then reduce to low and allow it to simmer for 30 minutes to an hour. If you feel the soup is still not smooth enough, you can run through the blender again or use and immersion blender. Season with additional salt and pepper to taste. Top with fresh basil and parmasan.enjoy!