Preheat your oven to 400°F (200°C). Spread the halved cherry tomatoes on a baking sheet, drizzle with 1 tablespoon of olive oil, and sprinkle with salt and pepper. Roast for 20-25 minutes, until the tomatoes are soft and slightly caramelized.

While the tomatoes are roasting, heat the remaining tablespoon of olive oil in a large pot over medium heat. Add the chopped onion and cook for 5-7 minutes, until soft and translucent. Add the minced garlic and cook for another 1-2 minutes, until fragrant.

Once the tomatoes are done roasting, add them to the pot along with their juices. Stir in the vegetable broth, tomato paste (if using), and sugar. Bring the mixture to a simmer and cook for 10-15 minutes, allowing the flavors to meld together.

Remove the pot from heat. Using an immersion blender, blend the soup until smooth and creamy. If using a regular blender, carefully transfer the soup in batches to blend. Be cautious as the soup will be hot.

Return the blended soup to the pot (if using a regular blender) and season with salt and pepper to taste. Stir in the fresh basil leaves and let them wilt slightly. If you want a creamier texture, add the heavy cream or coconut milk and stir well.

Ladle the soup into bowls, garnish with extra fresh basil, a drizzle of olive oil, or a swirl of cream, and serve with crusty bread or a grilled cheese sandwich for a complete meal.