Why it works: Butter and cheese are a kitchen classic. They rank in the top 8% of all ingredient pairs, and cooks put them together in 7,962 recipes. Both carry delta-dodecalactone, which smells sweet, creamy. The science ↓
Welsh Rarebit
Ingredients
Directions
Make the rarebit
Melt the butter in a chafing dish.
Add the dry mustard and stir well.
Gradually mix in the grated cheese until it begins to soften.
Pour in the ale or boiling water and stir vigorously.
Cook until the mixture is thick, smooth, and a rich yellow, about 3-4 minutes.
Serve
Serve on toast or with snowflake crackers if toast is unavailable.
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 + cheesetop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
-
Mustard + cheesetop 11% of all pairsSmell alikemoderateCooked together1,805 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Butter + mustardtop 22% of all pairsSmell alikemoderateCooked together8,003 recipes
Shared aroma: guaiacol (smoky, sweet).
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 it body, richness and its savoury flavour.
- Ale
- Thins the melted cheese into a smooth sauce and adds a malty flavour.
- Butter
- Adds fat that carries flavour and keeps the cheese sauce smooth and glossy.
The step that matters
Stirring in the cheese gradually. Adding cheese in small amounts over gentle heat lets it melt evenly. Dumping it in at once or overheating can make the proteins tighten and the sauce grainy or stringy.
Swap the mustard
How well each one fits the dish's main ingredients (butter, cheese):
- Potatofits better
- Mustardthe original
- Onionfits about as well
- Tomatofits less well
Fit is the average pairing score against butter, cheese. 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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