Sauté Aromatics: In a large, non-reactive pot (like an enameled Dutch oven) over medium heat, melt the butter. Add the chopped onion and sauté for a few minutes. Add the minced garlic and bell peppers, and continue to sauté, stirring occasionally, for about 10–12 minutes, until the onions are golden brown and the vegetables are softened.

Simmer Soup Base: Stir in the crushed tomatoes with their juice, chicken stock, oregano, basil, salt, and pepper. Bring the mixture to a boil. Stir in the sugar, then reduce the heat, partially cover the pot, and simmer for 10 minutes.

Blend (Optional): At this point, you can serve the soup chunky, or you can blend it for a smooth consistency. Carefully use an immersion blender until smooth. Alternatively, blend in batches in a standard blender (do not overfill, and vent the lid). Return the blended soup to the pot.

Finish and Serve: Stir in the heavy cream and return the soup to a gentle simmer. Ladle the hot soup into bowls. Top with grated Parmesan cheese and chopped basil, if desired. Season with additional salt and pepper to taste before serving.