Why it works: Onion and mustard match in chemistry and in kitchens. They rank in the top 6% of all ingredient pairs, and cooks put them together in 9,259 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Sauce Robert
Ingredients
Directions
In a stewpan, brown the diced onions in the butter.
Add the flour and cook until the mixture is a deep amber color.
Pour in the beef or veal gravy and let it simmer for 15 minutes.
Skim the sauce, then add salt and pepper to taste.
Just before serving, mix in the made mustard.
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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Onion + mustardtop 6% of all pairsSmell alikestrongCooked together9,259 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + beeftop 7% of all pairsSmell alikemoderateCooked together17,092 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Pepper + mustardtop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Beef + peppertop 10% of all pairsSmell alikemoderateCooked together18,971 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Onions
- Browned in butter to build a deep, sweet, savory base for the sauce.
- Butter
- Fat that browns the onions and carries their flavor through the sauce.
- Flour
- Thickens the sauce and, when cooked to amber, adds toasty color and flavor.
- Beef or veal gravy
- Liquid that forms the body of the sauce and adds meaty savory depth.
- Made mustard
- Adds sharp, tangy flavor that brightens the rich sauce.
The step that matters
Cooking the flour to deep amber. Flour must cook long enough to lose its raw taste and develop color, but not burn, since burnt flour turns the sauce bitter. Watching color closely keeps the flavor rich.
Swap the mustard
How well each one fits the dish's main ingredients (onion, butter, flour, beef, pepper):
- Potatofits better
- Chivefits better
- Leekfits better
- Mustardthe original
Fit is the average pairing score against onion, butter, flour, beef, 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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