Name: Deviled Egg Sandwiches
Ingredients: 4 hard-boiled eggs; ¼ cup salad oil; 2 teaspoons French mustard; ¼ teaspoon cayenne or paprika; ¼ teaspoon coarse sea salt; 1 teaspoon lemon juice; 8 slices buttered brown bread

Why it works: Mustard and lemon match in chemistry and in kitchens. They rank in the top 11% of all ingredient pairs, and cooks put them together in 3,816 recipes. Both carry eucalyptol, which smells eucalyptus, herbal. The science ↓

Deviled Egg Sandwiches

Ingredients

Directions

Make the filling

Remove the yolks from the hard-boiled eggs and mash them until they are a fine powder.
Mix the yolks with salad oil, French mustard, cayenne or paprika, coarse sea salt, and lemon juice until smooth.

Assemble

Spread the mixture between thin slices of buttered brown bread.

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 + lemontop 11% of all pairs

Smell alikestrong

Cooked together3,816 recipes

Shared aroma: eucalyptol (eucalyptus, herbal).
Egg + breadtop 13% of all pairs

Smell alikemoderate

Cooked together22,662 recipes

Shared aroma: (e)-2-octenal (fatty, green).
Mustard + breadtop 16% of all pairs

Smell alikemoderate

Cooked together1,484 recipes

Shared aroma: 2-acetyl-1-pyrroline (popcorn, roasted).
Egg + lemontop 19% of all pairs

Smell alikelow

Cooked together44,316 recipes

Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
Lemon + breadtop 20% of all pairs

Smell alikemoderate

Cooked together8,445 recipes

Shared aroma: 2-nonenal (fatty, green).

Egg and lemon barely smell alike, yet cooks put them together in 44,316 recipes: they work on texture and structure more than aroma.

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

What each ingredient does

Hard-boiled eggs: Yolks supply the rich, creamy base that gives the filling its body.
Salad oil: Adds fat that makes the yolk mixture smooth and spreadable.
French mustard: Adds sharpness and emulsifying help to keep the filling smooth.
Lemon juice: Adds acidity that brightens the rich yolk filling.

The step that matters

Mash the yolks until a fine powder. Finely broken-down yolks blend evenly with the oil and mustard, so the filling turns smooth rather than lumpy or grainy.

Swap the mustard

How well each one fits the dish's main ingredients (egg, lemon, bread):

Asparagusfits better
Shallotfits better
Spinachfits better
Mustardthe original

Fit is the average pairing score against egg, lemon, 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.

Brown Bread461 recipes

Lemon Sauce236 recipes

White Bread80 recipes

Bread Omelette60 recipes

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Deviled Egg Sandwiches