Why it works: Potato and onion are a kitchen classic. They rank in the top 3% of all ingredient pairs, and cooks put them together in 9,023 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Potato Soup
Ingredients
Directions
Mash the boiled potatoes and strain them through a sieve.
In a saucepan, combine the strained potatoes, milk, finely chopped onion, salt, pepper, and butter.
Heat the mixture over medium heat until it comes to a boil.
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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Potato + oniontop 3% of all pairsSmell alikemoderateCooked together9,023 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Milk + buttertop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Potato + peppertop 9% of all pairsSmell alikemoderateCooked together8,305 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Potato + milktop 9% of all pairsSmell alikemoderateCooked together3,611 recipes
Shared aroma: (e,z)-2,6-nonadienal (cucumber, melon).
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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Potatoes
- Form the body of the soup and thicken it as the starch releases when mashed.
- Milk
- Adds creamy richness and moisture, giving the soup its smooth liquid base.
- Butter
- Adds fat for a rich mouthfeel and a silky texture.
- Onion
- Contributes savory aroma and a mild sweetness as it cooks into the soup.
The step that matters
Heating the milk mixture to a boil. Milk scorches easily on the bottom of a pan over direct heat, so stirring and watching closely over medium heat prevents a burnt taste and keeps the texture smooth.
Swap the onion
How well each one fits the dish's main ingredients (potato, milk, butter, pepper):
- Capsicumfits better
- Asparagusfits about as well
- Tomatofits about as well
- Onionthe original
Fit is the average pairing score against potato, milk, 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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