Why it works: Onion and tomato are a kitchen classic. They rank in the top 8% of all ingredient pairs, and cooks put them together in 20,633 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Tomato Soup
Ingredients
Directions
Make the tomato base
Cut up the onion and fry it in oiled butter until brown.
Remove the onion and add the tomatoes.
Stew the tomatoes gently until tender.
Finish the soup
Pulp the tomatoes through a sieve.
Add the pulped tomatoes to the prepared stock.
Transcribed from a scanned cookbook and modernised for today's kitchens. Where the book gave no heat or time, or said "a moderate oven", the temperatures and times here may be modern equivalents rather than the book's own figures.
Photo for illustrative purposes only · Contact us to use it
Explore the science
The flavor team
The pairs that carry this dish. Each one is judged two ways: how much their aromas overlap, and how often cooks already put them together.
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Onion + tomatotop 8% of all pairsSmell alikemoderateCooked together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + buttertop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
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Butter + tomatotop 22% of all pairsSmell alikemoderateCooked together6,918 recipes
Shared aroma: 3-hexenal (apple, fruity).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Onion
- Browns in the fat to add sweet, savoury depth to the soup.
- Butter
- Fat that carries heat and helps the onion brown.
- Tomatoes
- Form the main body and tangy flavour of the soup.
- Stock
- Supplies the liquid base that the pulped tomatoes are added to.
The step that matters
Frying the onion until brown. Browning the onion through the Maillard reaction and caramelisation builds deeper flavour, but onions scorch easily, so they need steady heat and close watching.
Swap the tomato
How well each one fits the dish's main ingredients (onion, butter):
- Potatofits better
- Chivefits better
- Leekfits better
- Tomatothe original
Fit is the average pairing score against onion, butter. Candidates are from the same food group and used in at least 100 recipes.
“What each ingredient does” and “The step that matters” were written by Claude from this recipe’s own method and reviewed in samples by CompKitchen.
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