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 ↓
Brown Sauce
Ingredients
Directions
Melt the butter in a pan until it browns.
Add the flour and cook together until dark brown.
Pour in the soup stock and stir until thickened.
Season with pepper and salt to taste.
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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Flour + peppertop 19% of all pairsSmell alikemoderateCooked together50,459 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Butter + peppertop 21% of all pairsSmell alikemoderateCooked together85,593 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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
- Adds richness and flavour, and its milk solids brown to add nutty aroma.
- Flour
- Thickens the sauce as its starch swells in the hot liquid, and browns to deepen colour and flavour.
- Soup stock
- Provides the liquid base that the roux thickens into a sauce.
The step that matters
Browning the flour in the butter. Cooking the butter and flour together to dark brown develops nutty, roasted flavour and colour through the Maillard reaction and caramelisation. Stop too early and the sauce tastes raw and pale; go too far and it turns bitter and burnt.
“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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