Why it works: Watercress and mustard match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 293 recipes. Both carry coumarin, which smells sweet, hay. The science ↓
Cress Salad
Ingredients
Directions
Make the dressing
Mix equal parts of French Orleans vinegar, Provence oil, and tarragon vinegar in a bowl.
Season the mixture with coarse sea salt and mignonette pepper.
Prepare and serve
Thoroughly wash and trim the watercress and mustard cress, then drain well.
Pour the dressing over the cress and mix gently.
Transfer to a salad bowl and garnish with sliced hard-boiled egg before serving.
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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Watercress + mustardtop 1% of all pairsSmell alikestrongCooked together293 recipes
Shared aroma: coumarin (sweet, hay).
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Watercress + tarragontop 1% of all pairsSmell alikestrongCooked together108 recipes
Shared aroma: coumarin (sweet, hay).
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Mustard + tarragontop 1% of all pairsSmell alikestrongCooked together901 recipes
Shared aroma: methyleugenol (clove, spice).
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Tarragon + peppertop 5% of all pairsSmell alikestrongCooked together2,399 recipes
Shared aroma: estragole (anise, licorice).
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Vinegar + tarragontop 7% of all pairsSmell alikemoderateCooked together2,547 recipes
Shared aroma: isobutyraldehyde (malty, green).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Watercress
- Provides the fresh, peppery leaves that form the body of the salad.
- Mustard cress
- Adds a sharp, peppery bite that complements the watercress.
- Provence oil
- Carries the flavour of the dressing and coats the leaves, adding richness.
- French orleans vinegar
- Gives the dressing its acidity, which balances the oil and cuts richness.
The step that matters
Drain the cress well before dressing. Any water left on the leaves dilutes the vinegar and oil, so the dressing will not cling and will pool at the bottom of the bowl.
Swap the mustard
How well each one fits the dish's main ingredients (watercress, egg, vinegar, tarragon, pepper):
- Shallotfits about as well
- Mustardthe original
- Horseradishfits about as well
- Lettucefits about as well
Fit is the average pairing score against watercress, egg, vinegar, tarragon, 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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