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
Cook lentils until tender, then strain through a colander.
In a pot, combine lentils, nut butter, grated onion, and salt.
Add enough water to achieve a soupy consistency.
Thicken with white flour to prevent settling and serve hot.
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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Lentils + oniontop 8% of all pairsSmell alikestrongCooked together1,221 recipes
Shared aroma: coumarin (sweet, hay).
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Butter + oniontop 15% of all pairsSmell alikemoderateCooked together42,912 recipes
Shared aroma: decanal (soap, orange peel).
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Onion + flourtop 17% of all pairsSmell alikemoderateCooked together32,460 recipes
Shared aroma: isobutyraldehyde (malty, green).
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
- Lentils
- Form the body of the soup and give it its substance once cooked until tender.
- Nut butter
- Adds richness and fat, giving the soup a fuller, smoother mouthfeel.
- White flour
- Thickens the liquid so the soup holds together and resists settling.
- Grated onion
- Contributes savory flavor and aroma as it softens into the soup.
The step that matters
Thicken with white flour. Flour must be stirred in so it disperses without lumps; it thickens as the liquid heats, and added unevenly it clumps and leaves the soup thin in places.
Swap the onion
How well each one fits the dish's main ingredients (lentils, butter, flour):
- Kalefits better
- Arrowrootfits better
- Shallotfits better
- Onionthe original
Fit is the average pairing score against lentils, butter, flour. 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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