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 soup
Slice the potatoes, onion, and celery.
Heat the butter or fat in a stewpan, add the vegetables, and cook until the fat is absorbed, stirring frequently.
Add the stock and simmer until the vegetables are tender, about 1 hour.
Rub the mixture through a fine sieve and return it to the saucepan.
Finish and serve
Add the milk and bring to a boil.
Sprinkle in the sago and cook until transparent.
Season with salt and pepper to taste, and serve.
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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Celery + peppertop 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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Onion + celerytop 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
- Potatoes
- Break down during simmering to give the soup body and a thick, smooth texture.
- Butter or fat
- Carries flavour from the vegetables and coats them as they cook gently.
- Sago or tapioca
- Thickens the soup as its starch swells with heat, becoming transparent when cooked.
- Milk
- Adds richness and creaminess, softening the soup's flavour and mouthfeel.
- Onion
- Provides savoury aroma and sweetness as it softens in the fat.
The step that matters
Adding the sago. Sago and tapioca need sustained heat to swell and clear fully; if the soup is not kept at a steady simmer until they turn transparent, the starch stays chalky and the soup remains thin or grainy.
Swap the celery
How well each one fits the dish's main ingredients (milk, potato, onion, butter, pepper):
- Garlicfits better
- Parsleyfits better
- Thymefits better
- Celerythe original
Fit is the average pairing score against milk, potato, onion, butter, pepper. 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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