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 potato
Wash, peel, and soak the potato in cold water.
Boil the potato in water until very soft, then drain and mash it.
Make the soup
Cook the onion and celery in milk using a double boiler.
Add the mashed potatoes to the milk mixture.
Rub the mixture through a strainer.
Bring the strained mixture to a boil again.
Add butter and flour to bind the soup.
Season with pepper, celery salt, and salt.
Let the soup boil for 5 minutes before serving.
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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Pepper + celerytop 5% of all pairsSmell alikestrongCooked together16,012 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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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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Celery + oniontop 7% of all pairsSmell alikemoderateCooked together18,518 recipes
Shared aroma: guaiacol (smoky, sweet).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Potato
- Provides starch and body, thickening the soup and giving it a smooth, creamy texture when mashed.
- Milk
- Forms the liquid base and adds richness and a mild sweetness to the soup.
- Butter
- Adds fat and rich flavour, and helps bind the soup with the flour.
- Flour
- Thickens the soup by binding with the butter and liquid to give body.
The step that matters
Add butter and flour to bind the soup. Flour must be cooked into the butter and hot liquid so starch swells and thickens evenly; added raw or in clumps, it leaves a pasty, lumpy texture.
Swap the celery
How well each one fits the dish's main ingredients (potato, pepper, milk, onion, butter, flour):
- Parsleyfits better
- Thymefits better
- Garlicfits better
- Celerythe original
Fit is the average pairing score against potato, pepper, milk, onion, butter, flour. 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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