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 ↓
Green Pea Soup
Ingredients
Directions
Make the soup base
Wash the peas and cook them in boiling water until soft.
Press the peas through a coarse strainer to obtain 1 pint of stock and pulp.
Make the sauce
In a separate pan, melt the butter and stir in the flour to make a roux.
Gradually add the milk to the roux, stirring until smooth.
Combine and season
Combine the pea stock and pulp with the milk mixture.
Season with salt, pepper, and sugar to taste.
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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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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Flour + sugartop 15% of all pairsSmell alikemoderateCooked together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
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Peas + peppertop 15% of all pairsSmell alikemoderateCooked together5,331 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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
- Peas
- Provide the main flavour and body, and thicken the soup when pressed through a strainer.
- Butter
- Adds richness and carries flavour in the roux.
- Flour
- Thickens the milk into a smooth sauce when cooked with the butter.
- Milk
- Creates a creamy base that softens the soup's texture.
- Sugar
- Adds a touch of sweetness that balances the savoury peas.
The step that matters
Gradually add the milk to the roux, stirring until smooth. Adding liquid slowly while stirring lets starch granules disperse evenly in the roux. Dumping it in at once can trap flour in lumps that do not smooth out.
Swap the peas
How well each one fits the dish's main ingredients (butter, flour, milk, pepper, sugar):
- Almondfits better
- Chestnutfits better
- Milletfits better
- Peasthe original
Fit is the average pairing score against butter, flour, milk, pepper, sugar. 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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