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 ↓
Roux Brun
Ingredients
Directions
Make the roux
Melt the butter slowly in a saucepan.
Sprinkle in the flour and stir over low heat until uniformly browned, about 25 minutes.
Be careful not to scorch the mixture, as it will taste bitter.
Finish the sauce
Ensure the sauce is strong and well-flavored, then strain it.
Gradually stir the sauce into the roux, which should be slightly cooled.
Return the saucepan to heat and boil for 3 to 4 minutes until the sauce is rich and thickened as desired.
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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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 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
- Melts with the flour to form the base of the roux, adding richness and fat-based flavor.
- Flour
- Its starch thickens the sauce, and as it browns it develops nutty, toasted flavor.
The step that matters
Browning the roux without scorching. Flour browns through Maillard reactions and caramelization, which build color and nutty flavor. Past a point the starches burn, giving a bitter taste that cannot be removed, so low heat and constant stirring are needed.
“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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