Why it works: Butter and bread are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 27,232 recipes. Both carry delta-decalactone, which smells sweet, creamy. The science ↓
A Welsh Rare-Bit
Ingredients
Directions
The book gives no cooking times; the times in the steps were added in transcription, so check for doneness rather than trusting the clock.
Make the sauce
Melt the butter in a saucepan over medium heat.
Stir in the flour and cook for 1 minute.
Gradually add the milk, stirring constantly until thickened.
Add the cheese, mustard, cayenne pepper, and salt; stir until the cheese melts.
Assemble and serve
Toast the bread slices until golden brown.
Spread the cheese mixture over the toast.
Serve hot.
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 + breadtop 7% of all pairsSmell alikemoderateCooked together27,232 recipes
Shared aroma: delta-decalactone (sweet, creamy).
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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 + breadtop 7% of all pairsSmell alikemoderateCooked together2,130 recipes
Shared aroma: delta-decalactone (sweet, creamy).
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Cheese + buttertop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
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Mustard + peppertop 9% of all pairsSmell alikemoderateCooked together15,430 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 the sauce to provide rich flavor and a creamy, spreadable texture.
- Flour
- Thickens the butter and milk into a smooth sauce that holds the cheese.
- Butter
- Adds fat and richness, and forms the base for the flour roux.
- Milk
- Forms the liquid that thickens with flour into a creamy sauce.
The step that matters
Gradually add the milk, stirring constantly until thickened. Adding liquid all at once to a flour and butter mixture can form lumps. Adding it slowly while stirring lets the starch disperse evenly, giving a smooth sauce that thickens properly.
Swap the mustard
How well each one fits the dish's main ingredients (cheese, butter, flour, milk, pepper, bread):
- Potatofits better
- Capsicumfits better
- Tomatofits about as well
- Mustardthe original
Fit is the average pairing score against cheese, butter, flour, milk, pepper, bread. 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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