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 ↓
Fish Soup
Ingredients
Directions
Prepare and cook
Clean the fish thoroughly.
Place the fish in a pot with water, using 4 cups of water for each pound of fish.
Add the chopped onion and sweet herbs.
Cook until the fish is done and tasteless.
Strain and season
Strain the mixture through a colander.
Return the liquid to the pot, add butter, salt, and pepper to taste.
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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Fish + buttertop 12% of all pairsSmell alikemoderateCooked together4,488 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
-
Onion + buttertop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
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Fish + oniontop 19% of all pairsSmell alikelowCooked together1,924 recipes
Shared aroma: 2,4-decadienal (seaweed).
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Fish + peppertop 21% of all pairsSmell alikemoderateCooked together3,948 recipes
Shared aroma: 2-nonenal (fatty, green).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Fish
- Releases flavor and body into the cooking liquid, forming the base of the broth.
- Onion
- Adds aromatic sweetness to the broth as it softens during cooking.
- Sweet herbs
- Contribute aromatic flavor to the broth as they steep in the liquid.
- Butter
- Adds fat that gives the finished broth richness and a smoother mouthfeel.
The step that matters
Cook until the fish is done. Simmering gently rather than boiling hard keeps the fish tender and the broth clear. Vigorous boiling can break up the fish and cloud the liquid, while overcooking leaves little flavor in the fish.
Swap the onion
How well each one fits the dish's main ingredients (fish, butter, pepper):
- Capsicumfits better
- Potatofits better
- Tomatofits about as well
- Onionthe original
Fit is the average pairing score against fish, butter, pepper. 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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