Name: Lentil Soup
Ingredients: 2 onions, sliced; 2 carrots, sliced; 2 tablespoons dripping (or oil); 1 cup lentils; 4 cups water; herbs (such as thyme and bay leaf); 2 cloves; coarse sea salt to taste; black pepper to taste

Why it works: Thyme and clove match in chemistry and in kitchens. They rank in the top 2% of all ingredient pairs, and cooks put them together in 4,108 recipes. Both carry cuminaldehyde, which smells Spicy, cumin. The science ↓

Lentil Soup

Ingredients

Directions

Prepare the soup

Fry the sliced onions and carrots in the dripping until softened.
Add the lentils and water to a saucepan and bring to a simmer.

Simmer and finish

Once simmering, add the herbs and cloves tied in muslin, along with seasoning.
Simmer for 3 hours.
Pass the soup through a wire sieve and return it to the heat to warm before serving.

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.

Thyme + clovetop 2% of all pairs

Smell alikestrong

Cooked together4,108 recipes

Shared aroma: cuminaldehyde (Spicy, cumin).
Carrot + thymetop 3% of all pairs

Smell alikestrong

Cooked together4,563 recipes

Shared aroma: cuminaldehyde (Spicy, cumin).
Thyme + peppertop 4% of all pairs

Smell alikemoderate

Cooked together11,585 recipes

Shared aroma: beta-phellandrene (minty, terpene).
Clove + peppertop 5% of all pairs

Smell alikestrong

Cooked together17,451 recipes

Shared aroma: ethyl octanoate (fruity, wine).
Carrot + clovetop 5% of all pairs

Smell alikestrong

Cooked together5,873 recipes

Shared aroma: cuminaldehyde (Spicy, cumin).

Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs

What each ingredient does

Lentils: Break down during long simmering to thicken the soup and give it body.
Onions: Softened by frying, they build sweetness and a savoury base for the soup.
Carrots: Softened by frying, they add natural sweetness and body to the soup.
Dripping: Fat for frying the vegetables, carrying flavour and helping them brown and soften.

Swap the onion

How well each one fits the dish's main ingredients (carrot, lentils, thyme, clove, pepper):

Parsnipfits better
Turnipfits better
Leekfits better
Onionthe original

Fit is the average pairing score against carrot, lentils, thyme, clove, 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.