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
Prepare the potatoes
Pare the potatoes and boil them until tender.
Drain the water and mash the potatoes.
Make the soup
Add the butter, salt, pepper, and milk to the mashed potatoes.
Boil the mixture for 2-3 minutes.
Serve
Place the parsley in a soup tureen.
Pour the soup through a colander into the tureen.
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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Potato + parsleytop 5% of all pairsSmell alikemoderateCooked together2,855 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Butter + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Parsley + oniontop 9% of all pairsSmell alikemoderateCooked together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
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Potato + milktop 9% of all pairsSmell alikemoderateCooked together3,611 recipes
Shared aroma: (e,z)-2,6-nonadienal (cucumber, melon).
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, thickening into a smooth, starchy base when mashed.
- Butter
- Adds fat and richness, giving the soup a smooth, rounded mouthfeel.
- Milk
- Adds liquid and creaminess, softening the mashed potato into a pourable soup.
The step that matters
Boiling the mixture for 2-3 minutes. Milk can scorch or boil over on the bottom of the pan if left unattended. Stirring keeps the proteins from sticking and burning, and gentle heat keeps the soup smooth rather than curdled.
Swap the white pepper
How well each one fits the dish's main ingredients (potato, butter, milk, parsley, onion, mace):
- Thymefits better
- Nutmegfits better
- Marjoramfits better
- White pepperthe original
Fit is the average pairing score against potato, butter, milk, parsley, onion, mace. 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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