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 ↓
Onions, Stewed
Ingredients
Directions
Place the peeled onions in a stew pan and cover with cold water.
Boil the onions for 1 hour.
In a bowl, mix the butter and flour together, then stir the butter-flour mixture into the onions.
Add the milk, salt, and pepper, then let simmer for 30 minutes.
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
- Form the main body of the dish, becoming soft and sweet as they cook.
- Butter
- Adds richness and fat, carrying flavour and giving a smooth mouthfeel.
- All-purpose flour
- Thickens the cooking liquid into a light sauce as it combines with the butter.
- Milk
- Forms the creamy liquid that gives the sauce body and mild sweetness.
The step that matters
Adding the butter-flour mixture to the onions. Flour clumps if dropped in raw or unevenly mixed. Blending it with butter first and stirring it through the hot liquid helps it disperse and thicken smoothly.
Swap the onion
How well each one fits the dish's main ingredients (butter, flour, milk, pepper):
- Potatofits better
- Capsicumfits better
- Chivefits better
- Onionthe original
Fit is the average pairing score against butter, flour, milk, pepper. 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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