Gather your ingredients, including canned tomatoes (whole or crushed), onion, garlic, vegetable or chicken broth, butter, heavy cream, sugar, salt, pepper, and optional fresh herbs like basil or thyme.
In a large pot or Dutch oven, melt the butter over medium heat. Add diced onion and minced garlic to the pot, and sauté until softened and fragrant, about 3-5 minutes.
Pour in the canned tomatoes with their juices. If using whole tomatoes, you can crush them with your hands or a spoon for a chunkier soup, or blend them for a smoother texture.
Stir in the vegetable or chicken broth, sugar, salt, and pepper to taste. Bring the soup to a simmer, then reduce the heat to low and let it simmer for about 20-30 minutes to allow the flavors to meld together.
If you prefer a smooth tomato soup, use an immersion blender to puree the soup directly in the pot until smooth. Alternatively, you can carefully transfer the soup in batches to a blender and blend until smooth.
Stir in the heavy cream until fully incorporated. Adding cream gives the soup a rich and creamy texture, but you can adjust the amount to taste or omit it entirely for a lighter version.
Taste the soup and adjust the seasoning as needed, adding more salt, pepper, or sugar to balance the flavors to your liking. You can also stir in chopped fresh herbs like basil or thyme for added freshness.
Ladle the hot tomato soup into bowls and garnish with additional fresh herbs, a drizzle of cream, or a sprinkle of grated Parmesan cheese if desired. Serve hot with crusty bread or grilled cheese sandwiches for dipping.