Name: Cheese Sandwiches
Ingredients: 1 hard-boiled egg; ¼ pound common cheese, grated; ½ teaspoon salt; ½ teaspoon pepper; ½ teaspoon mustard; 1 tablespoon melted butter; 1 tablespoon vinegar or cold water

Why it works: Mustard and vinegar are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 14,067 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓

Cheese Sandwiches

Ingredients

Directions

Make the filling

Remove the yolk from the hard-boiled egg and place it in a small bowl.
Crumble the yolk and mix in the melted butter until smooth.
Add the salt, pepper, mustard, and grated cheese, mixing well after each addition.
Stir in the vinegar or cold water to achieve the desired thickness.

Assemble

Spread the mixture between two biscuits or pieces of oat-cake.

Recipe from a historical cookbook (Internet Archive).

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.

Mustard + vinegartop 7% of all pairs

Smell alikemoderate

Cooked together14,067 recipes

Shared aroma: isobutyraldehyde (malty, green).
Cheese + buttertop 8% of all pairs

Smell alikemoderate

Cooked together7,962 recipes

Shared aroma: delta-dodecalactone (sweet, creamy).
Pepper + mustardtop 9% of all pairs

Smell alikemoderate

Cooked together15,430 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Cheese + mustardtop 11% of all pairs

Smell alikemoderate

Cooked together1,805 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Cheese + vinegartop 12% of all pairs

Smell alikemoderate

Cooked together922 recipes

Shared aroma: 3-methylbutanol (malty, whiskey).

Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs

What each ingredient does

Hard-boiled egg: Yolk gives the filling a creamy, binding body once crumbled and blended with butter.
Common cheese: Provides the main savoury flavour and firm body to the spread.
Melted butter: Adds fat that makes the yolk mixture smooth and rich.
Vinegar or cold water: Thins the mixture, adjusting it to the desired spreadable consistency.

Swap the mustard

How well each one fits the dish's main ingredients (egg, cheese, pepper, butter, vinegar):

Capsicumfits about as well
Mustardthe original
Asparagusfits less well
Potatofits less well

Fit is the average pairing score against egg, cheese, pepper, butter, vinegar. 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.