Why it works: Capers and onion match in chemistry and in kitchens. They rank in the top 7% of all ingredient pairs, and cooks put them together in 1,381 recipes. Both carry coumarin, which smells sweet, hay. The science ↓
Piquante or Sharp Sauce
Ingredients
Directions
In a small saucepan, combine the onion and vinegar, then bring to a boil and reduce significantly.
Add the brown sauce, capers, gherkin, and salt and pepper if needed.
Bring to a boil again, then simmer for 5 minutes.
Serve warm.
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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Capers + oniontop 7% of all pairsSmell alikestrongCooked together1,381 recipes
Shared aroma: coumarin (sweet, hay).
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Sauce + caperstop 11% of all pairsSmell alikemoderateCooked together678 recipes
Shared aroma: ethanol (alcoholic, ethereal).
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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Capers + peppertop 12% of all pairsSmell alikemoderateCooked together2,088 recipes
Shared aroma: coumarin (sweet, hay).
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Vinegar + oniontop 14% of all pairsSmell alikemoderateCooked together18,226 recipes
Shared aroma: acetic acid (sour, vinegar).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Brown sauce
- Forms the base of the sauce, providing savoury depth and body.
- Vinegar
- Adds acidity that brightens the sauce and balances its richness.
- Capers
- Contribute a sharp, briny bite that gives the sauce its piquant character.
- Gherkin
- Adds tangy, crunchy pieces and extra acidity to the sauce.
- Onion
- Softens as it reduces with vinegar, adding sweetness and aromatic flavour.
The step that matters
Reducing the onion and vinegar. Boiling the vinegar down until significantly reduced concentrates its acidity and mellows its sharpness. Skipping or shortening this reduction leaves the sauce harsh and raw-tasting.
Swap the onion
How well each one fits the dish's main ingredients (sauce, vinegar, capers, pepper):
- Mustardfits better
- Shallotfits better
- Horseradishfits better
- Onionthe original
Fit is the average pairing score against sauce, vinegar, capers, 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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