Why it works: Butter and milk are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 81,283 recipes. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓
Welsh Rarebit
Ingredients
Directions
Make the rarebit
In a saucepan, mix the cheese, butter, ale, salt, mustard, pepper, and cayenne.
Stir over low heat until the mixture is smoothly melted.
Serve
Meanwhile, prepare two slices of toast and place them on a hot dish.
Once the rarebit is smooth, pour it over the toast and serve immediately.
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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Butter + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Cheese + buttertop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
-
Mustard + peppertop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Cheese + milktop 10% of all pairsSmell alikemoderateCooked together4,426 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
-
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 a smooth sauce that gives the rarebit its body and flavor.
- Butter
- Adds fat that keeps the melted cheese smooth and glossy rather than grainy.
- Ale
- Thins the cheese mixture and adds a slightly malty, tangy flavor.
The step that matters
Stir over low heat until smoothly melted. Cheese proteins toughen and separate when overheated, so low heat and constant stirring keep the sauce smooth instead of grainy or oily.
Swap the mustard
How well each one fits the dish's main ingredients (cheese, butter, pepper, egg, milk):
- Potatofits better
- Capsicumfits better
- Asparagusfits better
- Mustardthe original
Fit is the average pairing score against cheese, butter, pepper, egg, milk. 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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