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
Make the soup
Combine the tomatoes and boiling water in a pot and bring to a boil.
Add the baking soda; it will foam up.
Stir in the sweet milk, salt, pepper, and butter, then bring to a boil again.
Add the rolled crackers and serve hot.
Add the bread
Fry stale bread slices until brown, salt them, dice them, and add to the soup when serving.
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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Milk + buttertop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Tomato + peppertop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Tomato + breadtop 10% of all pairsSmell alikemoderateCooked together1,013 recipes
Shared aroma: 2-nonenal (fatty, green).
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Milk + breadtop 11% of all pairsSmell alikemoderateCooked together11,466 recipes
Shared aroma: 2-undecenal (sweet).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Tomatoes
- Provide the main body, acidity, and flavor of the soup.
- Baking soda
- Neutralizes tomato acid, causing foaming and mellowing the sharp tang.
- Sweet milk
- Adds creaminess and richness, turning the tomato base into a smooth soup.
- Butter
- Adds fat for richness and a silkier mouthfeel.
- Crackers
- Thicken the soup as they soak up liquid and soften.
The step that matters
Adding the baking soda. Baking soda reacts with the tomatoes' acid and releases carbon dioxide, so the mixture foams up sharply. Add it slowly to a pot with room to rise, or it can boil over; adding it to hot milk too early can curdle the soup.
Swap the tomato
How well each one fits the dish's main ingredients (milk, pepper, butter, bread):
- Capsicumfits about as well
- Potatofits about as well
- Tomatothe original
- Asparagusfits about as well
Fit is the average pairing score against milk, pepper, butter, 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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