Why it works: Parsley and pepper match in chemistry and in kitchens. They rank in the top 2% of all ingredient pairs, and 34,122 recipes mention both. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓
Tomato Soup Without Meat
Ingredients
Directions
In a soup pot, fry the onion in the dripping until reddish brown.
Add the tomatoes and stir until very hot.
Pour in the boiling water and add the parsley; stew for 30 minutes.
Strain the mixture, rubbing the tomato through a sieve into the hot liquid.
Return the liquid to the pot, season, and bring to a boil.
Stir in the floured butter and, a minute later, the rice.
Simmer for 10 minutes and then pour out.
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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Parsley + peppertop 2% of all pairsAroma overlapstrongMentioned together34,122 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
Tomato + ricetop 6% of all pairsAroma overlapstrongMentioned together3,065 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
-
Tomato + peppertop 7% of all pairsAroma overlapmoderateMentioned together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Tomato + oniontop 8% of all pairsAroma overlapmoderateMentioned together20,633 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Tomato + parsleytop 8% of all pairsAroma overlapmoderateMentioned together5,398 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Red tomatoes
- Provide the main body, moisture and tangy flavor of the soup.
- Butter
- Rolled in flour, it thickens the soup and adds richness.
- Onion
- Browning in dripping builds a sweeter, deeper savory base.
- Hot boiled rice
- Adds body and starch, helping the soup become thicker and smoother.
The step that matters
Stir in the floured butter. Flour clumps if added to liquid without being fully blended with the fat first, leaving lumps. Stirring it in gradually while the soup is hot and keeping it moving lets the starch hydrate evenly and thicken smoothly.
Flavor stand-ins for the onion
How well each one fits the dish's main ingredients (tomato, parsley, butter, flour, pepper, sugar, rice):
- Capsicumbetter flavor fit
- Okrabetter flavor fit
- Carrotbetter flavor fit
- Onionthe original
Fit is the average pairing score against tomato, parsley, butter, flour, pepper, sugar, rice. Candidates are from the same food group and used in at least 100 recipes. This compares flavor only: it does not check the job the ingredient does in the dish (bulk, moisture, acidity, structure).
“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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