Name: Tomato Soup
Ingredients: 1 shank of beef; 2 onions, chopped; 2 sticks of celery; 1 can of tomatoes; 2 teaspoons flour; water; salt and pepper to taste

Why it works: Celery and tomato are a kitchen classic. They rank in the top 4% of all ingredient pairs, and cooks put them together in 3,377 recipes. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓

Tomato Soup

Ingredients

Directions

Boil the shank of beef in water for 2 hours.
Add the chopped onions, celery, and canned tomatoes.
Strain the mixture and return the liquid to the pot.
Mix the flour with a little water to make a paste, then add to the soup.
Season with salt and pepper 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.

Photo for illustrative purposes only · Contact us to use it

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.

Celery + tomatotop 4% of all pairs

Smell alikemoderate

Cooked together3,377 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Celery + peppertop 5% of all pairs

Smell alikestrong

Cooked together16,012 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Beef + oniontop 7% of all pairs

Smell alikemoderate

Cooked together17,092 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Onion + celerytop 7% of all pairs

Smell alikemoderate

Cooked together18,518 recipes

Shared aroma: guaiacol (smoky, sweet).
Tomato + peppertop 7% of all pairs

Smell alikemoderate

Cooked together17,923 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

Beef shank: Slow boiling in water releases flavour and gelatin into the broth, giving body to the soup.
Flour: Mixed into a paste and stirred in, it thickens the liquid as it heats.
Tomatoes: Add acidity and a tomato flavour to the broth.

Swap the onion

How well each one fits the dish's main ingredients (beef, celery, tomato, flour, pepper):

Carrotfits better
Capsicumfits better
Okrafits better
Onionthe original

Fit is the average pairing score against beef, celery, tomato, flour, 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.