Why it works: Mustard and onion 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 ↓
Cheese Sandwiches
Ingredients
Directions
Make the cheese mixture
Melt the butter in a saucepan.
Add the grated cheese, paprika, mustard, Worcestershire sauce, and onion juice; stir until melted and smooth.
Beat the egg yolks and dilute them with the cream or milk; add to the cheese mixture.
Assemble
Let the mixture cool, then place it between slices of bread.
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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Mustard + oniontop 6% of all pairsSmell alikestrongCooked together9,259 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Butter + creamtop 8% of all pairsSmell alikemoderateCooked together41,516 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
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Butter + cheesetop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
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Sauce + creamtop 9% of all pairsSmell alikemoderateCooked together4,787 recipes
Shared aroma: ethanol (alcoholic, ethereal).
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Cheese + mustardtop 11% of all pairsSmell alikemoderateCooked together1,805 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
- Cheese
- Melts into the sauce to give the filling its body and rich flavor.
- Raw egg yolks
- Thicken the mixture as they set gently, giving it a smooth, spreadable texture.
- Cream or milk
- Dilutes the yolks and adds moisture so the filling stays smooth and creamy.
- Butter
- Adds fat and richness and helps the cheese melt smoothly.
The step that matters
Adding the egg yolks to the cheese mixture. Egg yolks scramble if they meet hot mixture too quickly. Diluting them with cream or milk first and adding them gently helps keep the filling smooth.
Swap the onion
How well each one fits the dish's main ingredients (butter, cheese, mustard, sauce, egg, cream, wheat):
- Chivefits better
- Asparagusfits better
- Horseradishfits better
- Onionthe original
Fit is the average pairing score against butter, cheese, mustard, sauce, egg, cream, wheat. 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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