Why it works: Mustard and garlic match in chemistry and in kitchens. They rank in the top 6% of all ingredient pairs, and cooks put them together in 4,053 recipes. Both carry linalool, which smells floral, citrus. The science ↓
Welsh Rarebit
Ingredients
Directions
Make the sauce
In a saucepan, melt the butter over low heat.
Add the ale, ground mustard, garlic, cayenne, and salt; stir to combine.
Gradually add the cheese, stirring until melted.
Serve
Serve immediately over buttered toast.
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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Mustard + garlictop 6% of all pairsSmell alikestrongCooked together4,053 recipes
Shared aroma: linalool (floral, citrus).
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Cheese + buttertop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
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Cheese + mustardtop 11% of all pairsSmell alikemoderateCooked together1,805 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Cheese + garlictop 18% of all pairsSmell alikemoderateCooked together2,738 recipes
Shared aroma: linalool (floral, citrus).
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Butter + garlictop 22% of all pairsSmell alikemoderateCooked together10,572 recipes
Shared aroma: linalool (floral, citrus).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- American cheese
- Melts into the sauce to provide the main body, richness, and savory flavor.
- Butter
- Adds fat and richness, helping the cheese melt smoothly into a silky sauce.
- Ale
- Thins the cheese mixture and adds a subtle malty, slightly acidic flavor.
- Ground english mustard
- Adds sharp, pungent heat that balances the richness of the cheese.
The step that matters
Gradually add the cheese over low heat. Cheese is sensitive to high heat. Adding it gradually over low heat lets it melt evenly into the liquid, while excessive heat can make it grainy, oily, or stringy.
Swap the garlic
How well each one fits the dish's main ingredients (cheese, butter, mustard):
- Capersfits better
- Thymefits better
- Tarragonfits better
- Garlicthe original
Fit is the average pairing score against cheese, butter, mustard. 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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