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
The book says “a hot oven”. The 400°F (200°C) in the steps is the modern equivalent, not the book's own figure.
Make the cheese sauce
Grate enough old cheese to cover toasted bread.
Melt the butter in a saucepan over low heat.
Add the milk and stir until smooth.
Mix in the grated cheese, salt, and cayenne pepper until fully melted.
Bake and serve
Spread the cheese mixture over the toast and place in a 400°F (200°C) oven for 4 minutes.
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).
-
Cheese + milktop 10% of all pairsSmell alikemoderateCooked together4,426 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
-
Cheese + peppertop 18% of all pairsSmell alikemoderateCooked together7,861 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Butter + peppertop 21% of all pairsSmell alikemoderateCooked together85,593 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Old cheese
- Provides the main flavor and, once melted, the body of the sauce.
- Butter
- Adds fat that enriches the sauce and helps it stay smooth.
- Milk
- Supplies the liquid that loosens the melted cheese into a spreadable sauce.
The step that matters
Melt the cheese gently over low heat. High heat tightens the cheese proteins and can make the fat separate, leaving the sauce grainy or oily instead of smooth.
“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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