Why it works: Mustard and vinegar are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 14,067 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓
Salad Dressing
Ingredients
Directions
Make the cooked dressing
In a saucepan, heat the vinegar and butter.
In a bowl, mix the flour, egg, mustard, sugar, salt, and pepper.
Add the mixed ingredients to the saucepan and let it boil until thick.
If desired, thin the dressing with a little cream.
Make the second dressing
For the second dressing, rub the hard-boiled egg yolks until smooth.
Mix in the English mustard, salt, raw egg yolks, and sugar.
Gradually add fresh sweet oil until the mixture thickens.
Add vinegar until the dressing reaches your desired consistency.
If you want more heat, add a little cayenne pepper.
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.
Photo for illustrative purposes only · Contact us to use it
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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Mustard + vinegartop 7% of all pairsSmell alikemoderateCooked together14,067 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Mustard + peppertop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + mustardtop 13% of all pairsSmell alikemoderateCooked together5,066 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Pepper + vinegartop 14% of all pairsSmell alikemoderateCooked together27,814 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
Flour and butter 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
- Flour
- Thickens the dressing as it cooks, giving it body.
- Egg
- Adds structure and richness, helping the cooked dressing set as it thickens.
- Butter
- Adds richness and a smooth mouthfeel to the cooked dressing.
- Hard-boiled egg yolks
- Form a smooth, creamy base that emulsifies with the oil.
- Raw egg yolks
- Act as an emulsifier, helping the oil and vinegar bind into a thick dressing.
- Fresh sweet oil
- Provides fat and body, thickening the dressing as it is added gradually.
The step that matters
Gradually add the oil. Adding oil slowly lets the yolks emulsify it into droplets; adding it too fast can break the mixture so it separates and fails to thicken.
Swap the mustard
How well each one fits the dish's main ingredients (flour, egg, sugar, pepper, vinegar, butter):
- Capsicumfits about as well
- Shallotfits about as well
- Mustardthe original
- Chivefits about as well
Fit is the average pairing score against flour, egg, sugar, pepper, vinegar, butter. 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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