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 Roux, or Thickening
Ingredients
Directions
Make the roux
Melt the butter slowly in a saucepan.
Dredge in flour until it forms a paste, stirring constantly.
Cook over high heat for a few minutes.
Reduce heat and stir until it turns light brown.
Store
Transfer to a jar for storage.
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
- Provides fat that coats flour particles and carries flavor as the roux browns.
- Flour
- Thickens the mixture into a paste and sets the body once cooked.
The step that matters
Reduce heat and stir until it turns light brown. Cooking flour in fat too hot too fast can scorch it or leave it unevenly colored. Lower heat and constant stirring let the starch and proteins brown gradually for a even, nutty color.
“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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