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 ↓
Mustard Sauce
Ingredients
Directions
Melt the butter in a small saucepan.
Blend in the flour, mustard, and salt until mixed.
Add the broth or water and bring to a boil.
Strain the sauce through a pointed strainer into a hot sauceboat.
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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Flour + mustardtop 13% of all pairsSmell alikemoderateCooked together5,066 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Butter + mustardtop 22% of all pairsSmell alikemoderateCooked together8,003 recipes
Shared aroma: guaiacol (smoky, sweet).
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 to form the fat base that the flour is blended into.
- Flour
- Thickens the sauce as it cooks with the liquid.
- French mustard
- Adds sharp, pungent flavor that defines the sauce.
- Broth or water
- Forms the liquid body of the sauce, which thickens when boiled.
The step that matters
Blending the flour into the melted butter. Stirring the flour into the butter cooks out its raw taste and coats the starch granules so they disperse without lumps when the liquid is added.
Swap the mustard
How well each one fits the dish's main ingredients (butter, flour):
- Shallotfits better
- Leekfits better
- Arrowrootfits better
- Mustardthe original
Fit is the average pairing score against butter, flour. Candidates are from the same food group and used in at least 100 recipes.
“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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