Why it works: Butter and flour are a kitchen classic. They rank in the top 12% of all ingredient pairs, and cooks put them together in 124,287 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓
Curry Sauce
Ingredients
Directions
Melt the butter in a saucepan.
Add the chopped onion and fry without browning for a few minutes.
Stir in the curry powder and a few drops of lemon juice, and continue to fry for 3-4 minutes.
Add the flour and fry for another minute.
Pour in the stock and add the chopped apple, stirring until boiling.
Simmer gently for about 30 minutes.
Season with salt and more lemon juice, adding more stock if the sauce is too thick.
Strain the sauce before serving.
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 + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Apple + lemontop 14% of all pairsSmell alikemoderateCooked together7,551 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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Butter + appletop 14% of all pairsSmell alikemoderateCooked together8,706 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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Butter + oniontop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
-
Butter + lemontop 16% of all pairsSmell alikemoderateCooked together41,227 recipes
Shared aroma: 3-hexenal (apple, fruity).
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 spices and onion and gives the sauce richness.
- Onion
- Softens as it cooks and adds sweetness and body to the sauce.
- Curry powder
- Provides the main spiced flavour, released more fully when fried in fat.
- Flour
- Thickens the sauce as it cooks with the stock.
- Apple
- Adds natural sweetness and softens into the simmering sauce.
- Stock
- Forms the liquid base of the sauce and is added to adjust thickness.
The step that matters
Fry the flour briefly, then add the stock gradually. Flour needs a short cook in fat to lose its raw taste and to mix smoothly. Adding liquid all at once can leave lumps, so keeping the sauce moving while it thickens gives a smooth result.
Swap the onion
How well each one fits the dish's main ingredients (butter, flour, apple, lemon):
- Arrowrootfits better
- Shallotfits better
- Parsnipfits better
- Onionthe original
Fit is the average pairing score against butter, flour, apple, lemon. 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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