Why it works: Onion and potato 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 ↓
Onion Soup
Ingredients
Directions
Prepare the soup
Peel and finely mince the onions and potatoes.
In a stew-pan, melt the dripping and sweat the onions and potatoes for 10 minutes without browning.
Add pepper, beef broth, sugar, bacon rind, and celery.
Simmer for 20 minutes until tender.
Finish and serve
Pass the soup through a sieve using a wooden spoon.
Grate the stale bread into the boiling milk and stir into the soup.
Serve very hot.
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.
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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Onion + potatotop 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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Onion + beeftop 7% of all pairsSmell alikemoderateCooked together17,092 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + celerytop 7% of all pairsSmell alikemoderateCooked together18,518 recipes
Shared aroma: guaiacol (smoky, sweet).
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Potato + beeftop 8% of all pairsSmell alikemoderateCooked together2,052 recipes
Shared aroma: sotolon (curry, maple).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Onions
- Provide the main body and sweet, savoury flavour of the soup as they soften.
- Potatoes
- Break down during simmering to thicken the soup and give it a smoother body.
- Beef broth
- Forms the liquid base of the soup and carries its savoury beef flavour.
- Stale bread crumb
- Absorbs liquid and thickens the soup once stirred in.
- Milk
- Adds richness and a softer, creamier texture to the finished soup.
The step that matters
Sweating the onions without browning. Browned onions turn bitter and darken the soup. Gentle heat softens them and draws out their natural sweetness, giving a mellow base for the broth.
Swap the celery
How well each one fits the dish's main ingredients (onion, potato, beef, sugar, milk):
- Garlicfits better
- Cinnamonfits better
- Celerythe original
- Gingerfits about as well
Fit is the average pairing score against onion, potato, beef, sugar, milk. 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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