Why it works: Lentils and flour match in chemistry and in kitchens. They rank in the top 5% of all ingredient pairs, and cooks put them together in 255 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓
Lentil, Soup
Ingredients
Directions
Prepare the lentils
Pick over and wash the lentils, then soak them for 3 hours.
Cook the lentils in boiling water until soft and the water reduces by half.
Rub the lentils through a strainer.
Finish the soup
Add the milk and bring to a boil.
Thicken the soup with flour cooked in butter.
Season with paprika, salt, and a little sugar.
Serve with croutons.
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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Lentils + flourtop 5% of all pairsSmell alikestrongCooked together255 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Milk + buttertop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
-
Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Milk + flourtop 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).
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
- Lentils
- Provide the main body and thickness of the soup once rubbed through a strainer.
- Milk
- Adds creaminess and softness to the soup, mellowing its earthy flavour.
- Flour
- Thickens the soup as it cooks in the butter, giving it a smoother body.
- Butter
- Carries the flour and adds richness and a rounded flavour to the soup.
The step that matters
Cook the flour in the butter before adding it. Cooking flour in fat first removes its raw taste and helps it blend smoothly without lumps, so the soup thickens evenly.
Swap the lentils
How well each one fits the dish's main ingredients (milk, flour, butter, sugar):
- Almondfits better
- Chestnutfits better
- Pistachiofits better
- Lentilsthe original
Fit is the average pairing score against milk, flour, butter, 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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