Why it works: Butter and milk are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 81,283 recipes. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓
Tomato Bisque Soup
Ingredients
Directions
Make the soup base
Boil tomatoes and soup stock together for 10 minutes.
Strain the mixture through a puree strainer.
Return the strained mixture to the fire and season with salt, pepper, and butter.
Add baking soda as you would in ordinary tomato soup.
Add milk and thicken
Stir in 1 quart of boiling milk.
Mix 2 tablespoons of arrowroot with a little cold water or milk, then add to the soup.
Stir constantly until the soup thickens.
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 + milktop 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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Pepper + arrowroottop 14% of all pairsSmell alikemoderateCooked together329 recipes
Shared aroma: coumarin (sweet, hay).
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Tomato + milktop 15% of all pairsSmell alikemoderateCooked together2,226 recipes
Shared aroma: 1-octen-3-one (mushroom, metallic).
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Tomato + arrowroottop 15% of all pairsSmell alikemoderateCooked together41 recipes
Shared aroma: coumarin (sweet, hay).
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 base.
- Milk
- Adds creaminess and mild sweetness, turning the tomato base into a bisque.
- Arrowroot
- Thickens the soup into a smooth, glossy texture when heated.
- Baking soda
- Neutralizes some of the tomato's acidity, mellowing the flavor and reducing curdling risk.
- Butter
- Adds richness and a rounder mouthfeel to the soup.
The step that matters
Stir constantly until the soup thickens. Arrowroot starch can clump or turn gummy if left unstirred, so constant stirring keeps it dispersed and gives a smooth thickened texture.
Swap the arrowroot
How well each one fits the dish's main ingredients (tomato, pepper, butter, milk):
- Capsicumfits better
- Potatofits better
- Carrotfits better
- Arrowrootthe original
Fit is the average pairing score against tomato, pepper, butter, 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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