Why it works: Butter and milk are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 81,283 recipes. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓
Omelet. No. 1
Ingredients
Directions
Make the onion base
In a stewpan, combine sliced onions and butter. Cover and cook until the onions are browned, stirring occasionally.
Stir in enough flour to create a stiff paste.
Gradually add water or milk until the mixture is the thickness of good cream.
Season with pepper and salt.
Finish and serve
Prepare hard-boiled eggs by shredding or cutting them into halves or quarters.
Combine the eggs with the onion mixture and serve.
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 + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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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).
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Flour + milktop 14% of all pairsSmell alikelowCooked together78,219 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Onion + buttertop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
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
- Onions
- Cooked slowly in butter, they brown and add sweetness and savory depth.
- Butter
- Cooks the onions and adds richness and flavor.
- Flour
- Thickens the mixture into a stiff paste that holds the dish together.
- Hard-boiled eggs
- Provide body and substance, mixed through the onion base.
The step that matters
Stirring in the flour and liquid gradually. Adding liquid slowly to the flour-and-butter mixture prevents lumps, so the sauce thickens evenly to the texture of good cream.
Swap the onion
How well each one fits the dish's main ingredients (butter, flour, milk, pepper, egg):
- Capsicumfits better
- Potatofits better
- Asparagusfits better
- Onionthe original
Fit is the average pairing score against butter, flour, milk, pepper, egg. 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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