Preheat the oven to 400°F (200°C). Cut the top off the garlic head, drizzle with olive oil, wrap in foil, and roast for 30-35 minutes until soft.

In a large pot, heat olive oil over medium heat. Add the diced tomatoes (with juices) and vegetable broth. Bring to a simmer.

Once the garlic is roasted, squeeze the cloves into the pot. Add sugar, salt, black pepper, and balsamic vinegar. Blend the soup until smooth using an immersion blender or a regular blender.

Stir in the heavy cream and heat through on low for about 5 minutes. Adjust seasoning if needed.

Ladle the soup into bowls and garnish with fresh basil and parsley. Serve hot.