Homemade tomato soup

Why canned tomatoes, even in season

Most of the year, canned whole tomatoes taste better than fresh ones. They are picked ripe and packed within hours, while supermarket tomatoes are picked green so they survive shipping. Whole peeled tomatoes are the best of the canned kinds: they are usually packed from better fruit than diced or crushed, and diced tomatoes often contain calcium chloride, which keeps the pieces firm and stops them breaking down in a soup. San Marzano-style tomatoes are sweeter and less acidic, but any good brand of whole peeled tomatoes works.

In late summer, when tomatoes are cheap and ripe, use about 4 pounds of fresh ones. Halve them, roast them cut side up at 425°F for 40 minutes, and add them to the pot in place of the cans.

Where the depth comes from

Tomato soup can taste thin and sharp, like warm tomato juice. Two steps fix that. Cooking the onion and carrot until they start to brown adds sweetness without sugar. Cooking the tomato paste until it darkens and sticks to the pot caramelizes it, and gives the whole pot a deeper, rounder flavor; our minestrone cooks its tomatoes down for the same reason. Do not skip either one to save five minutes.

The sugar is a correction, not an ingredient. Tomatoes vary a lot in acidity from can to can, so taste the soup after blending and only add it if the soup still tastes sharp.

Lighter or richer

• Without cream: leave it out and the soup drops to about 150 kcal a bowl. It is still good, just brighter and less velvety.
• With Greek yogurt: whisk 1/2 cup of plain Greek yogurt with a ladleful of the hot soup, then stir it in off the heat. Boiling it after that will make it curdle.
• Higher in protein: blend in a drained can of white beans with the tomatoes. That adds about 3 g of protein and 2 g of fiber a bowl, and makes the soup thicker and creamier without any cream.
• Cold and raw: in summer, blend raw tomatoes with olive oil instead, as in our keto gazpacho.
• Vegan: use olive oil in place of the butter, vegetable broth, and a few tablespoons of full-fat coconut milk or a handful of soaked cashews blended in with the tomatoes.

Tomato soup and grilled cheese

The pairing is an American classic for good reason: the acidity of the soup cuts through the cheese and butter. It does change the meal, though. A typical grilled cheese, made with two slices of bread, two ounces of cheddar and butter on the outside, adds around 400 to 500 kcal, more than twice what the soup has. For a lighter version, use one slice of whole-grain bread, an ounce of sharp cheese (sharp cheddar gives more flavor per ounce) and a light brush of oil, and toast it open-faced under the broiler. A slice of sourdough holds up best.

Keeping it

Four days in the fridge and three months in the freezer. Freeze it before adding the cream if you can, and stir the cream in when you reheat it: soups with cream sometimes separate a little when they thaw. A quick whisk brings them back together.

What it is worth nutritionally

A 1 1/2-cup bowl has about 190 kcal, with 4 g of protein, 12 g of fat and 17 g of carbohydrate, including about 4 g of fiber. That is a first course or a light lunch, not a full meal; pair it with a sandwich, a salad with some protein, or a chickpea salad. Cooked tomatoes are one of the best sources of lycopene, and the oil in the pot helps the body absorb it. Canned tomatoes and broth are both salty, so use low-sodium broth and taste before adding salt. The soup is vegetarian with vegetable broth, and gluten-free.