Heat olive oil in a large pot over medium heat.
Add the onion and cook for 4 to 5 minutes, stirring often, until softened.
Add the minced garlic and cook for about 30 seconds, until fragrant.
Add the peeled tomatoes with their juices.
Pour in the chicken stock or vegetable stock.
Add the sugar, oregano, crushed red pepper flakes, salt, and black pepper.
Stir, cover, and simmer for 20 to 25 minutes.
Add the heavy cream and fresh basil.
Blend with an immersion blender until smooth and creamy.
Taste and adjust seasoning as needed.
Serve warm with parmesan cheese, olive oil, herbs, croutons, or toasted bread.