Name: Tomato Bouillon with Bread Fingers
Ingredients: 12 tomatoes, sliced (or 1 can of tomatoes); 2 cups water; 1 onion, sliced; 1 bay leaf; 1 rounded teaspoon salt; ¼ teaspoon white pepper; 1 pint boiling water; 1 teaspoon beef extract (optional); 2 egg whites, slightly beaten

Why it works: Onion and beef are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 17,092 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓

Tomato Bouillon with Bread Fingers

Ingredients

Directions

Make the soup

In a saucepan, combine the tomatoes, 2 cups of water, onion, bay leaf, salt, and white pepper.
Boil rapidly for 10 minutes.
Press the mixture through a colander, using as much of the flesh as possible.
Add 1 pint of boiling water and the beef extract if desired.
Stir in the beaten egg whites and boil rapidly for 5 minutes.
Strain through two layers of cheesecloth.

Serve

Serve the clear soup with toasted bread fingers.

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.

Onion + beeftop 7% of all pairs

Smell alikemoderate

Cooked together17,092 recipes

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

Smell alikemoderate

Cooked together5,448 recipes

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

Smell alikemoderate

Cooked together20,633 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
White pepper + eggtop 21% of all pairs

Smell alikelow

Cooked together2,312 recipes

Shared aroma: 2-methylbutyraldehyde (malty, chocolate).
Onion + white peppertop 28% of all pairs

Smell alikelow

Cooked together2,395 recipes

Shared aroma: 2-methylbutyraldehyde (malty, chocolate).

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

What each ingredient does

Egg whites: Coagulate as they cook, trapping solids so the strained soup becomes clear.
Tomatoes: Provide the main body, flavour and acidity of the soup.
Onion: Adds savoury aroma and sweetness to the broth.

The step that matters

Stir in the beaten egg whites and boil rapidly for 5 minutes. Egg whites must be stirred in evenly before they set. As they cook they coagulate and trap suspended particles, which is what clarifies the soup when it is strained. Stirring too little or letting them clump leaves the broth cloudy.

Swap the white pepper

How well each one fits the dish's main ingredients (tomato, onion, beef, egg):

Garlicfits better
Cuminfits better
Celeryfits better
White pepperthe original

Fit is the average pairing score against tomato, onion, beef, egg. 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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Roast Beef211 recipes

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Tomato Bouillon with Bread Fingers