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 ↓
Buttered Onions
Ingredients
Directions
Boil the onions for a few minutes.
Pour off the water and add more boiling water and a little salt.
Boil until tender.
Drain the onions and dress with salt, pepper, and melted butter.
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 + buttertop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
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Pepper + buttertop 21% of all pairsSmell alikemoderateCooked together85,593 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Onions
- Cooking softens their texture and mellows their sharp flavour, making them tender and sweeter.
- Melted butter
- Adds fat and richness, coating the onions and carrying flavour.
The step that matters
Boil until tender. Onions go from tender to mushy within a short time. Checking them often and draining once they are soft keeps their shape and a pleasant texture.
Swap the onion
How well each one fits the dish's main ingredients (pepper, butter):
- Capsicumfits better
- Potatofits better
- Carrotfits about as well
- Onionthe original
Fit is the average pairing score against pepper, 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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