In a large pot, heat 2 tablespoons of olive oil over medium heat. Add 1 chopped onion and sauté for 5-7 minutes, stirring occasionally, until it becomes translucent and tender. Once the onion is softened, stir in 3 minced garlic cloves and cook for an additional minute until fragrant.

Add 1 can (28 ounces) of crushed tomatoes along with 2 cups of vegetable broth to the pot. Stir in 1 tablespoon of dried basil, 1 teaspoon of sugar, and season with salt and black pepper to taste. Increase the heat and bring the mixture to a gentle boil.

Once boiling, reduce the heat to low and let the soup simmer uncovered for 15-20 minutes. Stir occasionally to prevent sticking.

Remove the pot from heat and use an immersion blender to puree the soup until smooth, or carefully transfer batches to a regular blender.

Return the pureed soup to low heat and stir in 1 cup of heavy cream for a luscious finish. Heat through gently for about 2-3 minutes.

Ladle the warm, rich soup into bowls and, if desired, garnish with fresh basil leaves.