Heat olive oil in a large pot over medium heat. Add chopped onion and sauté until translucent, about 5 minutes.

Add minced garlic and cook for another minute until fragrant.

Pour in the canned tomatoes (with their juices) and vegetable broth. Stir well and bring to a simmer.

Add sugar, dried basil, salt, and pepper. Let the soup simmer for 15 minutes to blend the flavors.

Remove the pot from heat. Using an immersion blender, blend the soup until smooth and creamy.

Stir in the heavy cream and adjust seasoning if needed. Heat gently for another 2 minutes.

Ladle the soup into bowls, garnish with fresh basil leaves, and serve hot.