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 ↓
Potatoes a LA Lyonnaise
Ingredients
Directions
Fry the minced onion in hot butter until soft.
Add the cold sliced potatoes and stir until they are fried white.
Stir in the minced parsley 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.
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 + parsleytop 5% of all pairsSmell alikemoderateCooked together2,855 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Onion + parsleytop 9% of all pairsSmell alikemoderateCooked together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
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Butter + potatotop 13% of all pairsSmell alikemoderateCooked together6,456 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Onion + buttertop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Potatoes
- Form the bulk of the dish, browning on the surface as they fry in the butter.
- Onion
- Softens in the butter and adds sweetness and savoury depth to the potatoes.
- Butter
- Carries the heat and adds richness, helping the onion and potatoes brown.
The step that matters
Frying the cold sliced potatoes. Cold potatoes need enough hot butter and room to brown rather than steam. Stirring too often or crowding the pan keeps them pale and soft instead of golden.
Swap the parsley
How well each one fits the dish's main ingredients (onion, butter, potato):
- Garlicfits better
- Thymefits about as well
- Parsleythe original
- Capersfits less well
Fit is the average pairing score against onion, butter, potato. 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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