Why it works: Butter and bread are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 27,232 recipes. Both carry delta-decalactone, which smells sweet, creamy. The science ↓
Tomato Sotjp
Ingredients
Directions
The book says “a quick oven”. The 400°F (200°C) in the steps is the modern equivalent, not the book's own figure.
Make the soup
Combine the tomatoes and hot water in a pot and bring to a boil.
In a bowl, mix the flour, butter, and a tablespoon of the tomatoes until smooth.
Stir the mixture into the boiling tomatoes.
Add salt and sugar.
Boil for 15 minutes, then strain through a sieve.
Make the toasted bread cubes
Cut bread slices.
Butter the bread slices.
Cut the buttered slices into cubes.
Place the cubes butter side up in a pan.
Brown the cubes in a 400°F (200°C) oven.
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.
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Butter + breadtop 7% of all pairsSmell alikemoderateCooked together27,232 recipes
Shared aroma: delta-decalactone (sweet, creamy).
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Tomato + breadtop 10% of all pairsSmell alikemoderateCooked together1,013 recipes
Shared aroma: 2-nonenal (fatty, green).
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Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Flour + sugartop 15% of all pairsSmell alikemoderateCooked together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
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Butter + sugartop 17% of all pairsSmell alikemoderateCooked together98,233 recipes
Shared aroma: guaiacol (smoky, sweet).
Flour and butter 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
- Canned tomatoes
- Form the liquid base of the soup and provide its main flavor and acidity.
- Flour
- Thickens the soup as its starch swells when heated in the liquid.
- Butter
- Adds richness and helps the bread cubes brown when toasted.
- Sugar
- Softens the sharpness of the tomatoes, giving a rounder sweetness.
- Bread
- Forms crisp, browned cubes that add texture to the soup.
The step that matters
Mix the flour into a smooth paste before stirring it into the boiling tomatoes. Flour starch clumps when it hits hot liquid dry. Blending it with butter and some tomato first lets the starch separate and thicken the soup evenly.
Swap the tomato
How well each one fits the dish's main ingredients (flour, butter, sugar, bread):
- Shallotfits better
- Arrowrootfits better
- Leekfits better
- Tomatothe original
Fit is the average pairing score against flour, butter, sugar, bread. 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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