Name: Lentil Soup
Ingredients: ¼ pound lentils; 4 cups water; 1 onion, chopped; 2 carrots, chopped; Salt to taste; Pepper to taste; 1 slice of bread

Why it works: Lentils and carrot match in chemistry and in kitchens. They rank in the top 5% of all ingredient pairs, and cooks put them together in 505 recipes. Both carry coumarin, which smells sweet, hay. The science ↓

Lentil Soup

Ingredients

Directions

The book gives no cooking times; the times in the steps were added in transcription, so check for doneness rather than trusting the clock.

Prepare

Rinse the lentils under cold water.
In a pot, combine lentils, water, onion, and carrots.

Cook

Bring to a boil, then reduce heat and simmer for 30-40 minutes until lentils are tender.
Season with salt and pepper.

Serve

Serve hot with a slice of bread.

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 + 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).
Onion + carrottop 6% of all pairs

Smell alikemoderate

Cooked together21,601 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Lentils + oniontop 8% of all pairs

Smell alikestrong

Cooked together1,221 recipes

Shared aroma: coumarin (sweet, hay).
Onion + peppertop 11% of all pairs

Smell alikemoderate

Cooked together68,474 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 of the soup and thicken it as they break down while simmering.
Onion: Adds aromatic sweetness and savory depth as it softens in the broth.
Carrots: Contribute gentle sweetness and a firmer texture to the soup.