Why it works: Onion and pepper are a kitchen classic. They rank in the top 11% of all ingredient pairs, and cooks put them together in 68,474 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Onion Sauce
Ingredients
Directions
Prepare the onions
Boil three or four white onions until tender.
Mince the onions finely.
Make the sauce
Boil half a pint of milk.
Add butter and half the size of an egg to the milk.
Add salt and pepper to taste.
Stir in the minced onion.
Stir in a tablespoon of flour that has been moistened with milk.
Nutrition, whole recipe (rough)
What these numbers assume: 5 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Milk | 1 cup (244ml) whole | 149 |
| Egg | 1 large egg (50g) | 78 |
| Onion | 1 medium (110g) | 44 |
| Black Pepper | 1 tsp ground (2.3g) | 6 |
| Salt | 1 tsp (6g) | 0 |
One typical portion per ingredient; the recipe's quantities are not counted. A rough guide only, not for medical or dietary planning.
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. See the original page.
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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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Milk + eggtop 18% of all pairsSmell alikemoderateCooked together88,785 recipes
Shared aroma: 2-nonenal (fatty, green).
-
Milk + oniontop 20% of all pairsSmell alikemoderateCooked together13,418 recipes
Shared aroma: hexanal (green, grassy).
-
Milk + peppertop 22% of all pairsSmell alikemoderateCooked together26,984 recipes
Shared aroma: ethyl 2-methylbutyrate (fruity, apple).
-
Egg + peppertop 33% of all pairsSmell alikelowCooked together50,580 recipes
Shared aroma: 2-nonenal (fatty, green).
Egg and pepper barely smell alike, yet cooks put them together in 50,580 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
- White onions
- Provide the main flavour and soft, pulpy body once boiled and minced into the sauce.
- Milk
- Forms the liquid base of the sauce and is the medium the flour thickens.
- Butter (in the method)
- Adds richness and a smooth, rounded mouthfeel to the sauce.
- Flour (in the method)
- Thickens the milk as its starch swells when the sauce is heated.
The step that matters
Stir in the moistened flour. Dry flour added straight to hot liquid clumps, because its outer starch gels before the inside wets. Moistening it with milk first lets the starch disperse evenly, so the sauce thickens smoothly without lumps.
Swap the onion
How well each one fits the dish's main ingredients (milk, egg, pepper):
- Capsicumfits better
- Potatofits better
- Asparagusfits better
- Onionthe original
Fit is the average pairing score against milk, egg, 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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