01 - Preheat oven to 400°F.
02 - Slice the top off the garlic head to expose cloves, drizzle with olive oil, and wrap in foil.
03 - Place halved 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 for 35 to 40 minutes until tomatoes are soft and slightly caramelized and garlic is golden.
05 - Squeeze roasted garlic cloves from their skins.
06 - Transfer roasted vegetables and garlic to a large pot. Add vegetable broth, dried oregano, and sugar if using.
07 - Bring to a simmer over medium heat and cook for 10 minutes.
08 - Add basil leaves and blend with an immersion blender until silky smooth.
09 - Stir in cream or coconut cream if desired and adjust seasoning with salt and pepper.
10 - Serve hot, optionally garnished with extra basil or a drizzle of olive oil.