01 - Heat the oven to 400°F.
02 - Slice the top off the garlic head to expose cloves, drizzle with olive oil, then wrap tightly in foil.
03 - Place tomatoes cut side up, onion, carrot, and celery on a baking sheet. Drizzle with olive oil, season with salt and pepper, then add the wrapped garlic.
04 - Roast in the oven for 35 to 40 minutes until tomatoes are soft and caramelized and garlic is golden.
05 - Squeeze the roasted garlic cloves out of their skins.
06 - Transfer roasted vegetables and garlic to a large pot, add vegetable broth, oregano, and sugar if using; bring to a simmer over medium heat and cook for 10 minutes.
07 - Add fresh basil leaves and use an immersion blender or standard blender to puree until smooth.
08 - Stir in cream or coconut cream if desired, adjust seasoning with salt and pepper, then serve hot garnished with additional basil or a drizzle of olive oil.