Why it works: Pepper and tomato are a kitchen classic. They rank in the top 7% of all ingredient pairs, and 17,923 recipes mention both. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Tomato Soup
Ingredients
Directions
Make the soup
In a pot, combine the stock, tomatoes, sugar, salt, and pepper.
Cook for one hour.
In a bowl, mix the flour with cold water to create a thickening. Add the thickening to the soup and cook for an additional ten minutes.
Finish and serve
Strain the soup through a fine sieve.
Just before serving, stir in the cream 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 aroma chemistry they share, and how many recipes mention both.
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Pepper + tomatotop 7% of all pairsAroma overlapmoderateMentioned together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Sugar + creamtop 9% of all pairsAroma overlapmoderateMentioned together43,450 recipes
Shared aroma: 2,3-butanedione (butter, sweet).
-
Flour + sugartop 15% of all pairsAroma overlapmoderateMentioned together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
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Pepper + flourtop 19% of all pairsAroma overlapmoderateMentioned together50,459 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Flour + creamtop 20% of all pairsAroma overlapmoderateMentioned together30,481 recipes
Shared aroma: acetaldehyde (pungent, ethereal).
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.
- Flour
- Thickens the soup when cooked with liquid, giving it body.
- Stock
- Forms the liquid base that carries the other flavors.
- Cream
- Adds richness and a smoother, softer texture when stirred in.
The step that matters
Adding the flour thickening. Flour must be mixed smoothly with cold water before it goes into the hot soup, because dry or lumpy flour clumps and does not thicken evenly. Cooking it for the extra ten minutes lets the starch swell and lose its raw taste.
“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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