Why it works: Onion and pepper are a kitchen classic. They rank in the top 11% of all ingredient pairs, and cooks put them together in 68,474 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Boiled Onions
Ingredients
Directions
Peel the onions and soak them in cold water for 30 minutes.
Boil the onions in two pots of salted water until tender.
Drain the onions, season with pepper and salt, and cover with white sauce.
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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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + saucetop 19% of all pairsSmell alikelowCooked together10,474 recipes
Shared aroma: ethanol (alcoholic, ethereal).
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Pepper + saucetop 27% of all pairsSmell alikelowCooked together15,303 recipes
Shared aroma: ethanol (alcoholic, ethereal).
Onion and sauce barely smell alike, yet cooks put them together in 10,474 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
Swap the onion
How well each one fits the dish's main ingredients (pepper, sauce):
- Capsicumfits better
- Tomatofits better
- Mustardfits better
- Onionthe original
Fit is the average pairing score against pepper, sauce. Candidates are from the same food group and used in at least 100 recipes.
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