Name: Carrot and Lentil Soup
Ingredients: 3 quarts of stock or water; 1 pint of lentils; 4 carrots, sliced; 2 onions, sliced; 1 good lettuce, shredded; 2 tablespoons of cooked rice; 2 ounces of butter or fat; salt to taste; pepper to taste

Why it works: Lentils and lettuce share more aroma than cooks usually use. They rank in the top 1% of all ingredient pairs, and cooks put them together in 51 recipes. Both carry coumarin, which smells sweet, hay. The science ↓

Carrot and Lentil Soup

Ingredients

Directions

Prepare

Soak the lentils overnight, then wash and drain them well.

Make the soup

Heat the butter or fat in a saucepan, add the vegetables, and fry slowly for 15 minutes.
Add the lentils and stock or water, season with salt and pepper, cover, and simmer gently for 1 to 1.5 hours until the lentils are tender.
Pass the mixture through a sieve, return to the saucepan, and heat thoroughly.

Finish and serve

Add the cooked rice, season to taste, and serve.

Recipe from a historical cookbook (Internet Archive).

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.

Lentils + lettucetop 1% of all pairs

Smell alikestrong

Cooked together51 recipes

Shared aroma: coumarin (sweet, hay).
Lentils + carrottop 5% of all pairs

Smell alikestrong

Cooked together505 recipes

Shared aroma: coumarin (sweet, hay).
Carrot + peppertop 6% of all pairs

Smell alikestrong

Cooked together14,555 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Carrot + lettucetop 6% of all pairs

Smell alikestrong

Cooked together976 recipes

Shared aroma: 2-isobutyl-3-methoxypyrazine (green bell pepper, earthy).
Carrot + oniontop 6% of all pairs

Smell alikemoderate

Cooked together21,601 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).

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 protein-rich thickness of the soup as they soften and break down.
Carrots: Add sweetness and color, and give body once cooked and sieved.
Onions: Build a savory base of flavor when fried slowly in butter or fat.
Butter or fat: Carries flavor and gives the fried vegetables a rich, smooth mouthfeel.
Lettuce: Adds a mild, fresh vegetable flavor and extra bulk to the soup.

The step that matters

Simmer until the lentils are fully tender. Lentils must soften completely before sieving; undercooked lentils stay grainy and make the soup coarse and uneven in texture.

Swap the onion

How well each one fits the dish's main ingredients (lentils, carrot, lettuce, rice, butter, pepper):

Turnipfits better
Spinachfits better
Leekfits better
Onionthe original

Fit is the average pairing score against lentils, carrot, lettuce, rice, butter, pepper. 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.

Carrot Soup134 recipes

Rice Fritters84 recipes

Steamed Rice48 recipes

Rice Griddle Cakes28 recipes

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Carrot and Lentil Soup