Creamy tomato soup, finished off the boil

Canned crushed tomatoes are the right base on a weeknight. Fresh tomatoes only win in August, and even then they need longer to cook down. 800 g is two standard cans. The teaspoon of sugar is there to take the metallic edge off the tomato, not to make the soup sweet. If it still tastes sharp after 15 minutes, simmer longer. More sugar is the wrong fix.

Cook the onion until it is actually soft. A half-raw onion in a blended soup tastes like a bite of onion in every spoon, because the blender does not cook it.

Cream at the end

80 g of heavy cream is about 1/3 cup. A cup of heavy cream weighs 238 g on the heavy cream chart. Double cream is the UK equivalent and the weight is close enough to use the same 80 g. Stir it in off a hard boil. Boiled cream can split, and the soup looks speckled instead of smooth. You can leave the cream out and the soup is still good. It will taste brighter and thinner. The heavy cream substitutes and the double cream substitutes spell out what changes if you swap in milk or yogurt. Yogurt will curdle if the soup is boiling. Temper it with a spoon of hot soup first, then stir it in off the heat.

The butter is 30 g, about 2 tablespoons. The butter chart covers a different block size.

Blend properly. A few tomato chunks are fine in a rustic soup and wrong in this one. If you use a standing blender, do not fill it past halfway, and hold the lid with a towel. Hot soup expands.

Serve with a grilled cheese or plain toast. The soup keeps four days. It thickens in the fridge. Loosen it with a splash of water when you reheat it, and do not let it boil once the cream is in.