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
Cut the hard-boiled eggs into slices.
In a saucepan, melt ½ cup of butter over medium heat until it bubbles.
Add the chopped onion and cook until soft but not colored.
Stir in 1 teaspoon of flour and mix well.
Gradually add 1 cup of milk, stirring until smooth.
Add the egg slices and heat through.
Serve
Pour the mixture over hot buttered toast and season with pepper and salt.
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 and protein of the dish, sliced into the sauce.
- Butter
- Adds richness and fat, and coats the onion as it cooks.
- Flour
- Thickens the milk into a smooth, spoonable sauce.
- Milk
- Forms the liquid base of the sauce, giving it a creamy texture.
- Onion
- Adds savoury aroma and flavour as it softens in the butter.
The step that matters
Adding the milk. Flour needs to be added gradually to the hot butter and milk must be stirred in slowly so the starch disperses evenly. Adding it all at once can form lumps that are hard to smooth out.
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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