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 ↓
Split-pea Soup
Ingredients
Directions
Prepare the peas
Pick over and wash the split peas.
Soak the peas in cold water on the back of the stove for 1 hour.
Simmer the peas for 2 hours or until soft.
Make the soup
Rub the peas through a fine strainer and return to boil.
Add milk or water to achieve a thick soup consistency.
Cook the flour in the hot butter.
Add the cooked flour to the boiling strained soup.
Season with sugar, salt, and white pepper.
Serve
Serve with croutons or crisped crackers.
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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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + milktop 14% of all pairsSmell alikelowCooked together78,219 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + sugartop 15% of all pairsSmell alikemoderateCooked together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
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Peas + milktop 16% of all pairsSmell alikemoderateCooked together1,309 recipes
Shared aroma: hexanal (green, grassy).
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
- Dried split peas
- Form the body of the soup as they break down and thicken it when strained.
- Butter
- Carries the flour so it can be cooked smooth before thickening the soup.
- Flour
- Thickens the strained soup so it becomes creamy and holds a thick consistency.
- Milk
- Adds richness and softens the texture when used to thin the soup.
The step that matters
Add the cooked flour to the boiling strained soup. Stirring the flour into a hot liquid while it is already cooked in butter helps it disperse evenly, preventing lumps and a pasty texture as the soup thickens.
Swap the white pepper
How well each one fits the dish's main ingredients (peas, butter, flour, sugar, milk):
- Cinnamonfits better
- Nutmegfits better
- Gingerfits better
- White pepperthe original
Fit is the average pairing score against peas, butter, flour, sugar, milk. 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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