Why it works: Celery and parsley match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 6,810 recipes. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓
Potato Soup
Ingredients
Directions
Prepare the potatoes and milk
Cook the potatoes in boiling salted water until tender, then drain and rub through a strainer.
Scald the milk with the sliced onion, then remove the onion and add the milk to the potatoes.
Finish the soup
Melt the butter in a pan, stir in the flour, salt, pepper, celery salt, and cayenne, then add this mixture to the boiling soup.
Cook for 1 minute, then strain the soup and sprinkle in the chopped parsley.
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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Celery + parsleytop 1% of all pairsSmell alikestrongCooked together6,810 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Pepper + parsleytop 2% of all pairsSmell alikestrongCooked together34,122 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
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).
-
Pepper + celerytop 5% of all pairsSmell alikestrongCooked together16,012 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Potatoes
- Break down into a smooth, thick body once pressed through a strainer.
- Milk
- Provides the liquid base and creamy richness of the soup.
- Butter
- Carries fat for flavour and, with the flour, forms a roux that thickens the soup.
- Flour
- Thickens the soup when cooked in butter to form a roux.
The step that matters
Adding the butter and flour mixture to the boiling soup. Flour must be cooked in the butter first to form a roux; if it goes into the soup raw, it can clump and leave a pasty taste. Adding it to boiling soup while stirring helps it disperse and thicken evenly.
Swap the onion
How well each one fits the dish's main ingredients (potato, milk, pepper, celery, butter, flour, parsley):
- Carrotfits better
- Chivefits better
- Parsnipfits better
- Onionthe original
Fit is the average pairing score against potato, milk, pepper, celery, butter, flour, parsley. 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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