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 Soup
Ingredients
Directions
Prepare the base
Melt the butter in a saucepan.
Sauté chopped shallots or one white onion until soft.
Skin and slice the tomatoes, then add to the butter and stew until dissolved.
Boil the water or broth in a separate pot.
Cut the bread into dice and add to the boiling liquid.
Combine the contents of the saucepan with the boiling liquid and simmer together.
Strain and finish
Strain the mixture, pressing to extract all flavors.
Return to the saucepan, season with salt, and stir in the beaten egg yolk mixed with milk.
Heat until nearly boiling, then serve.
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.
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Butter + breadtop 7% of all pairsSmell alikemoderateCooked together27,232 recipes
Shared aroma: delta-decalactone (sweet, creamy).
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Butter + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Tomato + breadtop 10% of all pairsSmell alikemoderateCooked together1,013 recipes
Shared aroma: 2-nonenal (fatty, green).
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Bread + milktop 11% of all pairsSmell alikemoderateCooked together11,466 recipes
Shared aroma: 2-undecenal (sweet).
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Bread + eggtop 13% of all pairsSmell alikemoderateCooked together22,662 recipes
Shared aroma: (e)-2-octenal (fatty, green).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Tomatoes
- Provide the main flavor and body of the soup as they break down while stewing.
- Egg yolk
- Enriches the soup and thickens it gently when heated, adding richness.
- Milk
- Adds creaminess and softens the flavor, mellowing the tomato acidity.
- White bread
- Thickens the soup as it soaks up liquid and breaks down when simmered.
- Butter
- Adds fat and richness, carrying flavor as the tomatoes stew.
The step that matters
Adding the egg yolk and milk. Egg yolk thickens when heated but can curdle or scramble if the soup boils. Stir the mixture in gently and heat only until nearly boiling, as the record directs.
Swap the tomato
How well each one fits the dish's main ingredients (butter, bread, egg, milk):
- Potatofits better
- Asparagusfits better
- Leekfits about as well
- Tomatothe original
Fit is the average pairing score against butter, bread, egg, milk. 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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