Why it works: Mustard and pepper are a kitchen classic. They rank in the top 9% of all ingredient pairs, and cooks put them together in 15,430 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Welsh Rarebit
Ingredients
Directions
Make the sauce
Grate the cheese.
Beat the egg.
Put milk and mustard in a small saucepan and heat slowly, stirring all the time.
Mix the cornflour with a small amount of extra milk and add to the hot, not boiling saucepan; stir.
Add the grated cheese and continue stirring on low heat until it boils and thickens.
Add the beaten egg slowly while stirring.
Allow to cool.
Assemble and serve
Toast the bread on one side, and spread a liberal amount of the Welsh rarebit on the untoasted side.
Grill and serve immediately.
Or over vegetables, pour the hot sauce over the vegetables and serve immediately.
Nutrition, whole recipe (rough)
What these numbers assume: 8 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Flour | 1 cup (125g) all-purpose | 455 |
| Milk | 1 cup (244ml) whole | 149 |
| Cheddar Cheese | 1 oz (28g) | 113 |
| Cheese | 1 oz (28g) cheddar | 113 |
| Egg | 1 large egg (50g) | 78 |
| Black Pepper | 1 tsp ground (2.3g) | 6 |
| Mustard | 1 tsp (5g) yellow | 3 |
| Salt | 1 tsp (6g) | 0 |
One typical portion per ingredient; the recipe's quantities are not counted. A rough guide only, not for medical or dietary planning.
Steps grouped into stages for easier reading; the method is the source's own.
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.
-
Mustard + peppertop 9% of all pairsSmell alikemoderateCooked together15,430 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Milk + breadtop 11% of all pairsSmell alikemoderateCooked together11,466 recipes
Shared aroma: 2-undecenal (sweet).
-
Cheddar cheese + milktop 11% of all pairsSmell alikemoderateCooked together1,964 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
-
Cheddar cheese + mustardtop 11% of all pairsSmell alikemoderateCooked together708 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Egg + breadtop 13% of all pairsSmell alikemoderateCooked together22,662 recipes
Shared aroma: (e)-2-octenal (fatty, green).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Cheddar cheese
- Melts into the sauce to give it rich flavour and a thick, cohesive body.
- Milk
- Forms the liquid base that the cheese melts into and the cornflour thickens.
- Cornflour
- Thickens the sauce so it clings to the toast rather than running off.
- Egg
- Enriches the sauce and helps it set to a smooth, thick texture when stirred in.
- Mustard powder
- Adds sharp, savoury flavour that balances the richness of the cheese.
The step that matters
Adding the egg to the sauce. If the sauce is too hot when the beaten egg goes in, the egg proteins can scramble and make the sauce grainy. Adding it slowly while stirring, and letting the sauce cool first, helps keep it smooth.
Swap the mustard
How well each one fits the dish's main ingredients (cheddar cheese, milk, egg, pepper, bread):
- Capsicumfits better
- Potatofits better
- Asparagusfits better
- Mustardthe original
Fit is the average pairing score against cheddar cheese, milk, egg, 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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