Why it works: Tomato and pepper are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 17,923 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Tomato Soup
Ingredients
Directions
Make the soup
Combine tomatoes, salt, pepper, cold water, and the whole onion in a stew-pan.
Stir frequently until the soup boils, then cook for 15 minutes.
Beat butter and flour together in a bowl until light and smooth, then stir into the soup.
Cook for an additional 10 minutes, then remove the onion.
For a smooth soup, strain through a fine sieve.
Serve
Add stale bread pieces to the bottom of the soup tureen if desired.
Serve the soup with toasted or fried bread.
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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Tomato + peppertop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Tomato + oniontop 8% of all pairsSmell alikemoderateCooked together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Pepper + oniontop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Flour + sugartop 15% of all pairsSmell alikemoderateCooked together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
Butter and flour barely smell alike, yet cooks put them together in 124,287 recipes: they work on texture and structure more than aroma.
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Tomatoes
- Provide the main body, flavour and liquid base of the soup.
- Butter or drippings
- Adds fat and richness, carrying flavour through the soup.
- Flour
- Thickens the soup as it cooks, giving it a smoother body.
- Sugar
- Balances the acidity of the tomatoes with a touch of sweetness.
The step that matters
Stirring the butter and flour into the soup. Flour added directly to hot liquid can clump. Beating it smooth with butter first lets it disperse evenly and thicken the soup without lumps.
Swap the tomato
How well each one fits the dish's main ingredients (pepper, onion, butter, flour, sugar):
- Chivefits better
- Leekfits better
- Okrafits better
- Tomatothe original
Fit is the average pairing score against pepper, onion, butter, flour, sugar. 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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