Name: Puree of Tomato Au Crouton
Ingredients: 2 quarts of tomatoes; 1 small minced onion; 2 quarts of water or stock; 1 teaspoon of sugar; 1 teaspoon of salt; ½ cup of butter; ½ cup of flour; Salt and pepper to taste; Croutons for serving

Why it works: Tomato and pepper are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 17,923 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓

Puree of Tomato Au Crouton

Ingredients

Directions

Make the soup

Boil tomatoes, onion, stock, sugar, and salt gently for one hour.
Melt butter and mix with flour to make a thickening.
Add some of the tomato mixture to the butter and flour mixture instead of milk.
Pour the thickening into the soup and stir through a sieve.

Season and serve

Season with salt and pepper, and serve with croutons.

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.

Tomato + peppertop 7% of all pairs

Smell alikemoderate

Cooked together17,923 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).
Onion + peppertop 11% of all pairs

Smell alikemoderate

Cooked together68,474 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Butter + flourtop 12% of all pairs

Smell alikelow

Cooked together124,287 recipes

Shared aroma: isobutyraldehyde (malty, green).
Sugar + flourtop 15% of all pairs

Smell alikemoderate

Cooked together92,116 recipes

Shared aroma: phenylacetaldehyde (hawthorne, honey).

Butter and flour barely smell alike, yet cooks put them together in 124,287 recipes: they work on texture and structure more than aroma.

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

What each ingredient does

Tomatoes: Form the main body and flavor of the puree.
Butter: Enriches the soup and carries flavor when cooked with flour.
Flour: Thickens the soup once cooked into the butter as a roux.
Onion: Adds savory aroma and depth to the tomato base.

The step that matters

Cooking the flour and butter thickening. Flour must be cooked with the butter before liquid is added so it thickens smoothly without a raw, pasty taste or lumps.

Swap the tomato

How well each one fits the dish's main ingredients (onion, sugar, butter, flour, pepper):

Chivefits better
Leekfits better
Okrafits better
Tomatothe original

Fit is the average pairing score against onion, sugar, butter, 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.

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Puree of Tomato Au Crouton