Why it works: Butter and milk are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 81,283 recipes. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓
Curry Sauce
Ingredients
Directions
Brown the onion slices in butter.
Remove the onion and stir in flour, curry powder, and salt.
Add milk or cream and cook until thickened, similar to a white sauce.
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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Butter + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Flour + milktop 14% of all pairsSmell alikelowCooked together78,219 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Butter + oniontop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
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Onion + flourtop 17% of all pairsSmell alikemoderateCooked together32,460 recipes
Shared aroma: isobutyraldehyde (malty, green).
Butter and flour barely smell alike, yet cooks put them together in 124,287 recipes: they work on texture and structure more than aroma.
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Butter
- Carries the cooking fat and helps brown the onion for a deeper flavour.
- Onion
- Browning in butter adds sweet, savoury flavour to the sauce base.
- Flour
- Its starch thickens the liquid as it heats, giving the sauce body.
- Curry powder
- Supplies the spiced aroma and flavour that defines the sauce.
- Milk or cream
- Forms the liquid base that the flour thickens into a smooth sauce.
The step that matters
Cook until thickened after adding milk or cream. Flour starch only thickens fully when heated in liquid, and adding the liquid gradually while stirring keeps the sauce smooth. Too little heat or stirring leaves it thin or lumpy, while too much heat can scorch the milk.
Swap the onion
How well each one fits the dish's main ingredients (butter, flour, milk):
- Potatofits better
- Arrowrootfits better
- Leekfits better
- Onionthe original
Fit is the average pairing score against butter, flour, 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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