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 ↓
Pea Soup
Ingredients
Directions
Prepare the peas
Drain peas and rinse them.
Add sugar and cold water, then simmer for 20 minutes.
Rub the mixture through a sieve and reheat.
Finish the soup
Scald the milk with the onion, then remove the onion.
Add the milk to the pea mixture.
Thicken the soup with butter and flour cooked together.
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.
Photo for illustrative purposes only · Contact us to use it
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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Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Peas + oniontop 13% of all pairsSmell alikemoderateCooked together5,460 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Flour + milktop 14% of all pairsSmell alikelowCooked together78,219 recipes
Shared aroma: isobutyraldehyde (malty, green).
Flour and butter 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
- Peas
- Form the body and bulk of the soup once rubbed through a sieve.
- Butter and flour
- Cooked together they form a roux that thickens the soup.
- Milk
- Adds richness and a creamy, mellow body to the soup.
- Sugar
- Adds sweetness that balances the savoury flavour of the peas.
The step that matters
Thicken the soup with butter and flour cooked together. Flour must be cooked in the fat before liquid is added, so the starch swells smoothly without lumps and loses its raw taste. Stirring keeps the roux even.
Swap the peas
How well each one fits the dish's main ingredients (onion, sugar, flour, butter, milk, pepper):
- Almondfits better
- Chestnutfits better
- Milletfits better
- Peasthe original
Fit is the average pairing score against onion, sugar, flour, butter, 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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