Why it works: Pepper and parsley match in chemistry and in kitchens. They rank in the top 2% of all ingredient pairs, and cooks put them together in 34,122 recipes. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓
Cream Tomato Soup
Ingredients
Directions
Make the base
Thicken the milk with corn starch in a pot over medium heat.
Add butter, salt, pepper, parsley, and onion juice.
Combine and finish
Stir in the strained tomato juice and cook until heated through.
Slowly combine the tomato mixture with the milk while stirring continuously.
Just before serving, add baking soda and stir well.
Add a bay leaf for improved flavor, if desired.
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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Pepper + parsleytop 2% of all pairsSmell alikestrongCooked together34,122 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Corn + tomatotop 6% of all pairsSmell alikestrongCooked together2,099 recipes
Shared aroma: 2-nonenal (fatty, green).
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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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Pepper + tomatotop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + tomatotop 8% of all pairsSmell alikemoderateCooked together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Milk
- Forms the creamy liquid base that gives the soup its body and mild sweetness.
- Corn starch
- Thickens the milk as it heats, giving the soup a smooth, body-rich texture.
- Strained tomato juice
- Supplies the main tomato flavor and acidity that defines the soup.
- Baking soda
- Neutralizes some of the tomato's acidity, reducing the risk of the milk curdling.
- Butter
- Adds fat for richness and a rounder, smoother mouthfeel.
- Onion juice
- Adds a savory aroma and depth of flavor to the tomato and milk.
The step that matters
Slowly combine the tomato mixture with the milk. Tomato is acidic, and acid can cause hot milk proteins to curdle when they meet. Adding the mixture slowly while stirring continuously disperses the acid and heat gradually, keeping the soup smooth.
Swap the onion
How well each one fits the dish's main ingredients (milk, corn, butter, pepper, parsley, tomato):
- Capsicumfits better
- Potatofits better
- Carrotfits better
- Onionthe original
Fit is the average pairing score against milk, corn, butter, pepper, parsley, tomato. 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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