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
Prepare the base
Beat the eggs in a bowl.
Add the softened butter, mustard, and water; mix until smooth.
Stir in the vinegar and boiling water.
Make the dressing
Place the bowl over a kettle and stir until thickened like cream.
In a separate saucepan, warm the vinegar.
Add the beaten eggs and stir for a few minutes until it thickens like custard.
Finish
Mix in the salt, sugar, mustard, pepper, and remaining butter.
Stir well and pour into a container.
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.
-
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).
-
Vinegar + peppertop 14% of all pairsSmell alikemoderateCooked together27,814 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
Vinegar + sugartop 15% of all pairsSmell alikemoderateCooked together20,806 recipes
Shared aroma: beta-damascenone (apple, rose).
-
Egg + buttertop 17% of all pairsSmell alikemoderateCooked together118,967 recipes
Shared aroma: decanal (soap, orange peel).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Eggs
- Egg proteins set with gentle heat, thickening the dressing into a custard-like texture.
- Butter
- Adds fat for richness and a smooth, creamy mouthfeel.
- Mustard
- Adds sharp flavor and helps keep the dressing smooth and blended.
- Vinegar
- Provides acidity that gives the dressing its tang.
- Sugar
- Adds sweetness to balance the acidity of the vinegar.
The step that matters
Thickening the eggs over heat. Egg proteins thicken as they warm and set. Heating too fast or stirring too little can scramble them into lumps, so keep the heat gentle and stir constantly until the mixture coats a spoon.
Swap the mustard
How well each one fits the dish's main ingredients (egg, butter, vinegar, sugar, pepper):
- Capsicumfits better
- Mustardthe original
- Cucumberfits about as well
- Shallotfits less well
Fit is the average pairing score against egg, butter, vinegar, sugar, pepper. 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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