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 ↓
Potage Parmentier
Ingredients
Directions
Make the soup
Peel the potatoes and place them in a saucepan with the onions and about 3 pints of cold water.
Bring to a boil and cook for about 35 minutes until the vegetables are very tender.
Pass the mixture through a sieve back into the saucepan.
Finish and serve
Return to the heat, add salt, pepper, and butter.
When boiling, stir in the cream.
Serve immediately with croutons.
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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Nutmeg + peppertop 7% of all pairsSmell alikestrongCooked together13,015 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Cream + buttertop 8% of all pairsSmell alikemoderateCooked together41,516 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
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Potato + nutmegtop 8% of all pairsSmell alikemoderateCooked together1,052 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Potato + peppertop 9% of all pairsSmell alikemoderateCooked together8,305 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
- Break down into starch to give the soup its thick, smooth body.
- Butter
- Adds fat and richness, rounding out the flavor and mouthfeel.
- Cream or rich milk
- Adds fat and richness, giving a smoother, silkier finish.
- Onions
- Provide sweetness and aromatic flavor as they soften in the broth.
The step that matters
Pass the mixture through a sieve. Straining only works well when the vegetables are fully tender, since firm pieces will not press through and the soup stays grainy.
Swap the onion
How well each one fits the dish's main ingredients (potato, nutmeg, cream, pepper, butter):
- Spinachfits better
- Chivefits better
- Leekfits about as well
- Onionthe original
Fit is the average pairing score against potato, nutmeg, cream, 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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