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 sauce
Melt the butter in a saucepan.
Add the grated cheese, mustard, salt, and paprika; stir until nearly melted.
Pour in the scalded milk or cream and mix well.
Just before serving, stir in the beaten egg.
Serve
Serve the mixture over 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.
-
Butter + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
-
Cheese + buttertop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
-
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).
-
Egg + buttertop 17% of all pairsSmell alikemoderateCooked together118,967 recipes
Shared aroma: decanal (soap, orange peel).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Grated cheese
- Melts into the sauce to provide rich flavour and a smooth, creamy body.
- Egg
- Thickens the sauce slightly and adds richness when stirred in gently at the end.
- Butter
- Adds fat and richness, helping the cheese melt smoothly into the sauce.
- Scalded milk or cream
- Forms the liquid base that loosens the cheese into a pourable, creamy sauce.
- Mustard
- Adds sharpness that balances the richness of the cheese and butter.
The step that matters
Stir in the beaten egg just before serving. Egg proteins set when heated, so adding it to a very hot sauce or boiling it can curdle or scramble the egg. Adding it last, over gentle heat, lets it thicken the sauce smoothly.
Swap the mustard
How well each one fits the dish's main ingredients (cheese, egg, butter, milk):
- Potatofits better
- Asparagusfits better
- Capsicumfits better
- Mustardthe original
Fit is the average pairing score against cheese, egg, butter, 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.
More welsh rarebit recipes
You might also like
The free Flavor Lab newsletter: one surprising pairing a week and the molecular reason it works, in 60 seconds. No spam, unsubscribe anytime.
Prefer an account? Create a free account to save pairings and unlock the full chemistry.
Macaroni and Cheese102 recipes
Cheese Making50 recipes
Cheese Fritters34 recipes
Cheese Omelette31 recipes