Add the butter and olive oil into a big pot. Once the butter is melted, add the chopped onion. Stir and cook until fragrant. Next, add the minced garlic. Keep stirring to keep it from burning. Cook for about 5 minutes.

Add the whole peeled tomatoes and the water or chicken stock. Next, season it with sugar, salt, and black pepper. Bring to a boil and let it simmer for 30 minutes to reduce the liquid and intensify the flavors.

Reduce to a simmer and continue cooking for 30 minutes. Add the thyme and oregano and mix.

Remove from heat. Mash the soup with a potato ricer, masher, or immersion blender. Be careful not to over-blend, as the olive oil can become bitter.

Add the heavy cream and mix. Taste and adjust the seasonings if needed. Fill a bowl, top with basil leaves, and serve.