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
Beat the eggs until light.
Add mustard, salt, vinegar, and cayenne pepper; mix well.
Place the mixture in a dish over boiling water and warm through.
Add butter and cook until slightly thicker than custard, stirring constantly.
If desired, boil until thicker, then thin with milk or cream.
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).
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Mustard + peppertop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Vinegar + peppertop 14% of all pairsSmell alikemoderateCooked together27,814 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
Egg + buttertop 17% of all pairsSmell alikemoderateCooked together118,967 recipes
Shared aroma: decanal (soap, orange peel).
-
Pepper + buttertop 21% of all pairsSmell alikemoderateCooked together85,593 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Eggs
- Coagulate as they heat, thickening the dressing into a creamy custard-like texture.
- Vinegar
- Adds acidity that balances the richness of the eggs and butter.
- Butter
- Adds fat for smoothness and a rounder, richer mouthfeel.
- Mixed mustard
- Adds sharpness and helps emulsify the dressing for a smoother texture.
The step that matters
Add butter and cook until slightly thicker than custard, stirring constantly.. Egg proteins set with gentle heat. Over-heating or failing to stir can scramble the eggs into lumps, so constant stirring over moderate heat keeps the dressing smooth.
Swap the mustard
How well each one fits the dish's main ingredients (egg, vinegar, pepper, butter):
- Capsicumfits better
- Mustardthe original
- Shallotfits about as well
- Cucumberfits about as well
Fit is the average pairing score against egg, vinegar, pepper, 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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