Italian tomato and basil soup

Ingredients

• 10 ml (2 tsp)olive oil
• 1 smallred onion, diced
• 794 g (28 oz)no-salt-added tomato purée
• 240 ml (1 cup)low-sodium vegetable stock
• 1.25 ml (¼ tsp)salt
• 80 ml (⅓ cup)fresh basil leaves, thinly sliced
• 10 ml (2 tsp)balsamic vinegar

Instructions

1. 1

   Soften the onion

   Heat the olive oil in a large saucepan over a medium heat. Add the diced onion and cook, stirring occasionally, until completely softened, about 8 minutes.

2. 2

   Simmer the soup

   Add the tomato purée, vegetable stock and salt. Bring the saucepan to the boil over a high heat, then reduce the heat to medium-low and simmer uncovered for about 5 minutes, until the flavours have combined. For a thinner soup, add more stock.

3. 3

   Add basil and vinegar

   Stir in the basil and balsamic vinegar.

4. 4

   Serve the soup

   Ladle into bowls and serve hot or cold.

What is Italian tomato and basil soup?

Tomato soup with basil draws on familiar Italian flavours: tomato, aromatic herbs and a little acidity. This version uses tomato purée as its base, with onion softened in olive oil before the stock is added.

A brief simmer brings the ingredients together without making the method complicated. Basil and balsamic vinegar stirred in at the end give the soup its final fragrant, tangy notes.

Nutrition and macros by portion

The nutrition label shows one serving as written: 110 calories, 4g protein, 21g carbs, 3g fat.

The tomato purée supplies most of the carbohydrates, while the olive oil provides most of the fat. The stock and tomatoes contribute some protein, but this soup is not especially protein-rich; pair it with a protein-containing side such as a grilled cheese sandwich or add beans to the meal.

The tomato base

Tomato purée: the no-salt-added kind lets you control the seasoning yourself. Its smooth texture also means there is no need for a separate blending step in this method.

Vegetable stock: low-sodium stock adds savoury depth while leaving room to adjust the salt. Add extra stock if you prefer a thinner consistency.

Soften the onion gently

Onion: cook it in the oil over a medium heat, stirring now and then, for about 8 minutes. Aim for fully softened pieces rather than browned ones; lowering the heat a little can help if they start colouring too quickly.

This first stage builds a mellow base for the tomatoes. Give the onion time to soften before adding the purée and stock.

Keep the simmer brief

After bringing the mixture to the boil over a high heat, lower the heat to medium-low. Simmer uncovered for about 5 minutes, just long enough for the flavours to combine.

A long simmer is not required by this method. Keep the soup at a gentle simmer rather than a vigorous boil.

Finish with basil and vinegar

Basil: thinly sliced fresh leaves add their aroma when stirred in at the end. Adding them after the simmer helps keep their flavour noticeable.

Balsamic vinegar: its acidity balances the rich tomato flavour. Stir it in with the basil, then taste the soup before serving and adjust the seasoning if needed.

Ways to serve it

Hot soup: serve it in bowls with a grilled cheese sandwich or a fresh salad for a simple meal. You can also spoon it over pasta as a tomato sauce.

Cold soup: chill it for a refreshing summer side. If serving it cold, check the seasoning again, as cold temperatures can make flavours seem less pronounced.

Recipe notes & tips

• Dice the onion evenly so it softens at a similar pace.
• Stir the onion occasionally during its 8-minute cooking time.
• Use low-sodium stock so you can control the final saltiness.
• Add extra stock a little at a time if you want a thinner soup.
• Slice the basil finely so it distributes easily through the soup.
• Taste and adjust the seasoning before serving, especially if serving the soup cold.

Variations

• Garlicky: add minced garlic while the softened onion is still in the pan, before adding the tomato purée.
• Spicy: stir in crushed red pepper for a little heat.
• Pasta sauce: simmer the soup until it reaches a consistency that coats pasta, adding stock only as needed.
• Chilled: cool and refrigerate the soup, then serve it cold as a summer side.
• Heartier bowl: add cooked beans when you stir in the basil and vinegar.

Common mistakes to avoid

• Browning the onion: keep the heat moderate and stir occasionally so it softens without taking on too much colour.
• Boiling too hard: reduce the heat after the boil so the soup simmers gently.
• Overcooking the basil: stir it in at the end rather than simmering it with the tomato base.
• Making it too thick: add more vegetable stock gradually until the consistency suits you.
• Under-seasoning cold soup: taste and adjust the salt after chilling, before serving.

How to store

Refrigerate leftovers in a covered container for up to 3 days. Reheat gently in a saucepan until hot, or serve chilled; stir well before serving either way.

Frequently asked questions