Heat the olive oil in a large pot over medium heat.
Add the chopped onion and sauté until translucent, about 5 minutes.
Stir in the minced garlic and cook for an additional minute, until fragrant.
Pour in the canned tomatoes with their juice, followed by the vegetable broth.
Bring the mixture to a simmer and cook for about 20 minutes.
Blend the soup using an immersion blender until smooth.
Stir in the heavy cream and bring the soup back to a gentle simmer.
Season with salt and pepper to taste, adjusting as necessary.
Serve hot, garnished with fresh basil, if desired.