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 ↓
White Sauce
Ingredients
Directions
Make the sauce
Melt the butter in a saucepan over low heat.
Stir in the flour until well combined.
Slowly add the tepid water while stirring briskly.
Cook for about 10 minutes until the sauce is smooth and thick.
Season with salt and pepper.
Finish and combine
Remove from heat and slowly pour the sauce into a bowl with the raw egg yolk and vinegar, beating continuously.
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).
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Pepper + vinegartop 14% of all pairsSmell alikemoderateCooked together27,814 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Flour + eggtop 15% of all pairsSmell alikelowCooked together106,462 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Butter + eggtop 17% of all pairsSmell alikemoderateCooked together118,967 recipes
Shared aroma: decanal (soap, orange peel).
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Flour + peppertop 19% of all pairsSmell alikemoderateCooked together50,459 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
- Adds richness and flavour while forming the base of the roux with the flour.
- All-purpose flour
- Thickens the sauce when cooked with melted butter and liquid.
- Tepid water
- Hydrates the flour so the mixture thickens into a smooth sauce.
- Raw egg yolk
- Adds richness and emulsifies the sauce, giving it a silkier body.
The step that matters
Pouring the sauce into the egg yolk and vinegar. Adding hot sauce to the yolk too quickly, or without constant beating, can scramble the egg and leave lumps. Pouring slowly while beating keeps the yolk smooth and evenly blended into the sauce.
“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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