Why it works: Onion and parsley are a kitchen classic. They rank in the top 9% of all ingredient pairs, and cooks put them together in 25,843 recipes. Both carry 2,4-decadienal, which smells seaweed. The science ↓
White Sauob
Ingredients
Directions
Make the sauce
Combine one quart of milk, two tablespoons of flour, one of butter, a slice of onion, and a sprig of parsley.
Boil a few minutes until smooth.
Add the whites of three eggs beaten stiff.
Finish and serve
Pour over the fish.
Put in the oven a few minutes to brown if desired.
Nutrition, whole recipe (rough)
What these numbers assume: 5 portions
| Ingredient | Portion assumed | kcal |
|---|---|---|
| Flour | 1 cup (125g) all-purpose | 455 |
| Milk | 1 cup (244ml) whole | 149 |
| Egg | 1 large egg (50g) | 78 |
| Onion | 1 medium (110g) | 44 |
| Parsley | 1 tbsp chopped fresh (3.8g) | 1 |
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.
-
Onion + parsleytop 9% of all pairsSmell alikemoderateCooked together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
-
Flour + parsleytop 12% of all pairsSmell alikemoderateCooked together16,675 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Milk + flourtop 14% of all pairsSmell alikelowCooked together78,219 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + eggtop 15% of all pairsSmell alikelowCooked together106,462 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + oniontop 17% of all pairsSmell alikemoderateCooked together32,460 recipes
Shared aroma: isobutyraldehyde (malty, green).
Milk and flour barely smell alike, yet cooks put them together in 78,219 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
- Milk
- Forms the liquid base that thickens into the sauce as it heats.
- Flour
- Thickens the sauce as its starch swells when heated in the liquid.
- Eggs
- Beaten whites fold in air for a lighter, foamier texture.
The step that matters
Boil until smooth. Flour must be fully dispersed and heated long enough for its starch to swell and thicken the milk. Stopping early leaves the sauce thin or lumpy.
Swap the onion
How well each one fits the dish's main ingredients (milk, flour, parsley, egg):
- Shallotfits better
- Arrowrootfits better
- Chivefits better
- Onionthe original
Fit is the average pairing score against milk, flour, parsley, 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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