Why it works: Cheese and mustard are a kitchen classic. They rank in the top 11% of all ingredient pairs, and cooks put them together in 1,805 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Welsh Rarebit
Ingredients
Directions
The book says “the hot oven”. The 400°F (200°C) in the steps is the modern equivalent, not the book's own figure.
Prepare
Preheat the oven to 400°F (200°C).
In a bowl, combine the grated cheese, mustard, coarse sea salt, and cayenne.
Assemble and bake
Heap the cheese mixture onto slices of buttered toast.
Place the toast in the hot oven for a few moments until the cheese begins to melt.
Serve
Serve immediately.
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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Cheese + mustardtop 11% of all pairsSmell alikemoderateCooked together1,805 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
- Grated cheese
- Melts into a creamy, savoury topping that browns and sets on the toast.
- Mustard
- Adds sharp, tangy flavour that balances the richness of the cheese.
- Buttered toast
- Provides a crisp, absorbent base that holds the melted cheese topping.
The step that matters
Placing the toast in the hot oven. Cheese left in the oven too long becomes greasy and separates as its fats overheat, so watch closely and stop once it just begins to melt.
“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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