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 ↓
White Soup
Ingredients
Directions
Make the stock
Combine 5 cups of white stock, ½ tablespoon coarse sea salt, ½ teaspoon peppercorns, 1 slice onion, and 1 stalk celery in a pot.
Simmer for 30 minutes, then strain the mixture.
Make the soup
In a separate pan, melt 3 tablespoons butter and whisk in 4 tablespoons flour to create a roux.
Gradually add 2 cups scalded milk to the roux, stirring until thickened.
Dilute the slightly beaten egg yolks with some hot soup, then add this mixture to the remaining soup.
Strain again and adjust seasoning with salt and pepper if necessary.
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 + celerytop 7% of all pairsSmell alikemoderateCooked together18,518 recipes
Shared aroma: guaiacol (smoky, sweet).
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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
- Butter
- Enriches the roux and adds richness and flavour to the soup.
- Flour
- Forms a roux with the butter that thickens the milk into a smooth body.
- Milk
- Forms the creamy base of the soup once thickened with the roux.
- Egg yolks
- Add richness and further thicken the soup when tempered with hot liquid.
The step that matters
Adding the egg yolks. If the beaten yolks meet hot soup directly they can scramble. Diluting them with some hot soup first gradually raises their temperature, so they blend smoothly and thicken the soup without curdling.
Swap the celery
How well each one fits the dish's main ingredients (onion, butter, flour, milk, egg):
- Nutmegfits better
- Capersfits better
- Cinnamonfits better
- Celerythe original
Fit is the average pairing score against onion, butter, flour, milk, 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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