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
Prepare
Chop the onion and cook it in boiling water for 5 minutes.
Drain the liquid from the can of tomatoes.
Press the tomatoes through a colander.
Make the soup
Add the tomatoes and their liquid to the onion, along with the soup stock.
Season with salt and pepper.
Cook for 15 minutes.
Serve
Serve with crackers or toasted bread cut into squares.
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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Onion + tomatotop 8% of all pairsSmell alikemoderateCooked together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Tomato + breadtop 10% of all pairsSmell alikemoderateCooked together1,013 recipes
Shared aroma: 2-nonenal (fatty, green).
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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + breadtop 15% of all pairsSmell alikemoderateCooked together8,676 recipes
Shared aroma: 2,4-decadienal (seaweed).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Onion
- Softens as it cooks, adding sweetness and a mellow aromatic base to the soup.
- Tomatoes
- Provide the main body and bright acidity that define the soup's flavour.
- Soup stock
- Forms the liquid base and adds savoury depth to the soup.
Swap the onion
How well each one fits the dish's main ingredients (tomato, pepper, bread):
- Capsicumfits better
- Eggplantfits better
- Carrotfits better
- Onionthe original
Fit is the average pairing score against tomato, pepper, bread. 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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