Why it works: Butter and bread are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 27,232 recipes. Both carry delta-decalactone, which smells sweet, creamy. The science ↓
Nuns' Toast
Ingredients
Directions
Make the sauce
Slice the hard-boiled eggs.
Melt the butter in a saucepan until bubbling.
Add the chopped onion and cook without browning.
Stir in the flour and cook briefly.
Pour in the milk and stir until smooth.
Add the egg slices and heat through.
Season with pepper and salt.
Serve
Serve the sauce over hot 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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Butter + breadtop 7% of all pairsSmell alikemoderateCooked together27,232 recipes
Shared aroma: delta-decalactone (sweet, creamy).
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Butter + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Milk + breadtop 11% of all pairsSmell alikemoderateCooked together11,466 recipes
Shared aroma: 2-undecenal (sweet).
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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
Butter and flour barely smell alike, yet cooks put them together in 124,287 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
- Provide the main body of the dish, sliced and warmed through in the sauce.
- Butter
- Carries the onion and flour and adds richness to the sauce.
- Onion
- Adds savory aroma and flavor to the sauce base.
- Flour
- Thickens the butter and milk into a smooth, lightly bodied sauce.
- Milk
- Forms the liquid of the sauce, which thickens when combined with the flour.
The step that matters
Cook the onion without browning. Browning would add bitter, toasted flavors that clash with the delicate white sauce. Gentle cooking softens the onion and keeps the sauce pale and mild.
Swap the onion
How well each one fits the dish's main ingredients (egg, butter, flour, milk, pepper, bread):
- Capsicumfits better
- Asparagusfits better
- Potatofits better
- Onionthe original
Fit is the average pairing score against egg, butter, flour, milk, 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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