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 ↓
Chili Sauce
Ingredients
Directions
Prepare
Boil the ripe tomatoes and rub them through a sieve.
Make the sauce
Add the onions, chopped red peppers, vinegar, sugar, and salt to the tomatoes.
Boil the mixture for two hours.
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.
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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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + vinegartop 14% of all pairsSmell alikemoderateCooked together18,226 recipes
Shared aroma: acetic acid (sour, vinegar).
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Pepper + vinegartop 14% of all pairsSmell alikemoderateCooked together27,814 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Ripe tomatoes
- Form the sauce base and provide the main body and flavour.
- Vinegar
- Adds acidity that sharpens flavour and helps preserve the sauce.
- Sugar
- Adds sweetness that balances the acidity of the vinegar and tomatoes.
- Onions
- Add savoury flavour and body as they soften during the long boil.
- Red peppers
- Add sweetness, colour and a mild peppery flavour to the sauce.
The step that matters
Boil the mixture for two hours. A long, steady boil lets water evaporate so the sauce thickens and the flavours concentrate. Too little cooking leaves it thin and sharp, while the sugar and vinegar can scorch if the heat is too high and the pan is not stirred.
Swap the onion
How well each one fits the dish's main ingredients (tomato, pepper, vinegar, sugar):
- Capsicumfits better
- Cucumberfits better
- Mustardfits better
- Onionthe original
Fit is the average pairing score against tomato, pepper, vinegar, 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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