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

Stir in the minced garlic and cook for one minute until fragrant.

Add the crushed tomatoes, vegetable broth, and black pepper. Bring the mixture to a gentle simmer and cook for 20 minutes.

Remove the pot from the heat and stir in the chopped fresh basil leaves.

Use an immersion blender to carefully purée the soup until completely smooth and creamy.

Stir in the heavy cream and gently warm over low heat for 2 minutes. Do not let the soup boil after the cream is added.

Serve hot in bowls, garnished with extra fresh basil leaves and a generous handful of croutons.