Why it works: Mustard and pepper are a kitchen classic. They rank in the top 9% of all ingredient pairs, and cooks put them together in 15,430 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Welsh Rarebit
Ingredients
Directions
Make the sauce
Heat the ale in a saucepan until boiling.
Cut the cheese into small pieces.
Beat the egg and add it to the cheese along with the mustard, salt, and cayenne pepper.
Pour the cheese mixture into the boiling ale, stirring constantly until smooth.
Serve
Serve immediately on toast or crackers.
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 + peppertop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Cheese + mustardtop 11% of all pairsSmell alikemoderateCooked together1,805 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Cheese + peppertop 18% of all pairsSmell alikemoderateCooked together7,861 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Cheese + eggtop 28% of all pairsSmell alikemoderateCooked together6,253 recipes
Shared aroma: 2-nonenal (fatty, green).
-
Egg + mustardtop 28% of all pairsSmell alikemoderateCooked together9,210 recipes
Shared aroma: (e)-2-octenal (fatty, green).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Cheese
- Melts into the ale to form the smooth, rich body of the sauce.
- Ale
- Liquid base that melts the cheese and adds a malty, slightly acidic flavour.
- Egg
- Adds richness and helps thicken the sauce as it sets.
- Mustard
- Adds sharp, pungent flavour that balances the richness of the cheese.
The step that matters
Pour the cheese mixture into the boiling ale, stirring constantly until smooth.. Cheese proteins can seize and turn grainy or stringy if overheated or added too quickly. Constant stirring keeps the cheese emulsified and evenly distributed, producing a smooth sauce.
Swap the mustard
How well each one fits the dish's main ingredients (cheese, egg, pepper):
- Capsicumfits better
- Asparagusfits about as well
- Mustardthe original
- Spinachfits about as well
Fit is the average pairing score against cheese, egg, 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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