Place a large pot on medium heat. Add butter and olive oil. Let them melt slowly. The mix gives a rich base. Stir gently to avoid burning. This step builds flavor for the soup.

Add chopped onion to the pot. Cook for about 5 minutes. Stir often until soft and light golden. This brings sweetness to the soup. Do not rush this step.

Add minced garlic to the pot. Cook for one minute only. Stir well so it does not burn. Garlic adds a deep and warm flavor.

Now add chopped tomatoes. Stir everything together. Let them cook for 10 minutes. The tomatoes will soften and release juices. This is the heart of the soup.

Add vegetable broth to the pot. Stir well to combine all flavors. Bring the mixture to a gentle boil. Then reduce heat and let it simmer slowly.

Add salt, pepper, and sugar. Stir well. Taste and adjust if needed. The sugar helps balance the tangy tomatoes.

Turn off the heat. Use a blender or hand blender. Blend until smooth and creamy. Be careful when blending hot soup.

Pour the soup back into the pot. Add heavy cream and stir. Heat gently for 2–3 minutes. Do not boil after adding cream.

Pour the soup into bowls. Garnish with fresh basil if you like. Serve warm with bread or grilled cheese.