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 overnight in the water.
Boil the lentils for three to four hours, adding water to maintain the same level.
Strain the lentils; you should have four cups after straining.
Make the soup
Melt the butter in a saucepan.
Add the flour to the melted butter and mix well.
Slowly add the hot lentils to the butter and flour mixture.
Stir until it thickens.
Allow the mixture to boil thoroughly.
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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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Lentils + buttertop 27% of all pairsSmell alikemoderateCooked together486 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
- Provide the main body and starch that give the soup its substance.
- Butter
- Adds richness and fat that carries flavour in the soup.
- Flour
- Thickens the soup as its starch swells in the hot liquid.
The step that matters
Slowly add the hot lentils to the butter and flour mixture. Adding the hot liquid gradually while stirring keeps the flour evenly dispersed, so its starch can swell smoothly instead of clumping into lumps.
Swap the lentils
How well each one fits the dish's main ingredients (butter, flour):
- Almondfits better
- Macadamia nutfits better
- Cashew nutfits better
- Lentilsthe original
Fit is the average pairing score against 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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