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 ↓
To Make Roux
Ingredients
Directions
In a small saucepan, melt the butter over medium heat until it reaches the boiling point.
Sprinkle in the flour and mix well with a whisk until the flour is cooked but not browned.
Stir in a small amount of the sauce or soup until smooth and thin enough to add to the main sauce or soup.
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
- Melted fat that coats flour particles, carrying flavor and richness into the roux.
- Flour
- Starch that thickens the fat and, once hydrated, sets the sauce or soup as it cooks.
The step that matters
Cooking the flour without browning it. Flour must cook long enough to lose its raw starchy taste, but over-browning weakens its thickening power and changes the color of the final sauce. Keep the heat moderate and whisk constantly.
“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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