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
Wash and peel the potatoes, then soak them in cold water for 30 minutes.
Boil the potatoes until very soft.
Drain the water from the potatoes and mash them.
Make the soup
In a double boiler, cook the onion and celery with the milk.
Add the boiling milk and seasonings to the mashed potatoes.
Strain the mixture and bring it back to a boil.
Melt the butter in a small saucepan, then add the flour and mix well.
Stir the flour mixture into the boiling soup and let it boil for 5 minutes.
Serve
Serve very hot.
If the soup is too thick, add more hot milk.
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 + celerytop 7% of all pairsSmell alikemoderateCooked together2,047 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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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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Onion + celerytop 7% of all pairsSmell alikemoderateCooked together18,518 recipes
Shared aroma: guaiacol (smoky, sweet).
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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
- Provide the starchy body that becomes a thick, smooth soup when mashed.
- Milk
- Supplies liquid and richness, giving the soup its creamy texture.
- Butter
- Adds fat and flavour, and carries the flour into a smooth roux.
- Flour
- Thickens the soup as its starch swells in the hot liquid.
The step that matters
Stirring the flour mixture into the soup. Flour clumps if added raw or unevenly. Cooking it in melted butter first and whisking it into boiling liquid, then boiling for a few minutes, lets the starch hydrate and thicken the soup smoothly.
Swap the white pepper
How well each one fits the dish's main ingredients (potato, milk, onion, celery, flour, butter):
- Parsleyfits better
- Thymefits better
- Garlicfits better
- White pepperthe original
Fit is the average pairing score against potato, milk, onion, celery, flour, 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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