Why it works: Milk and butter 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 ↓
Onion Sauce
Ingredients
Directions
Prepare the onions
Peel the onions and boil them until tender.
Press the water from the onions and chop them finely.
Make the sauce
Combine the chopped onions with the hot milk in a saucepan.
Add the butter, salt, and pepper, and stir well.
Serve
Serve the sauce with boiled veal, poultry, or mutton.
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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Milk + buttertop 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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Onion + buttertop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
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Onion + milktop 20% of all pairsSmell alikemoderateCooked together13,418 recipes
Shared aroma: hexanal (green, grassy).
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Butter + peppertop 21% of all pairsSmell alikemoderateCooked together85,593 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- White onions
- Provide the main body of the sauce and a mild, sweet flavour once cooked soft.
- Milk
- Supplies the liquid and creamy base that carries the softened onion.
- Butter
- Adds fat for a rich mouthfeel and a smoother, more rounded finish.
The step that matters
Pressing the water from the onions. Boiled onions hold a lot of water. If it is not pressed out, the hot milk is diluted and the sauce turns thin and watery instead of creamy and well flavoured.
Swap the onion
How well each one fits the dish's main ingredients (milk, butter, pepper):
- Potatofits better
- Capsicumfits better
- Tomatofits about as well
- Onionthe original
Fit is the average pairing score against milk, butter, 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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