Why it works: Celery and parsley match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 6,810 recipes. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓
Tomato Soup
Ingredients
Directions
Prepare the broth
Wash the beef in cold water and place it in a soup kettle with enough cold water to cover it.
Skim the surface as it heats until no more scum rises.
Cover and let it boil slowly for 5 hours.
Add the vegetables and tomatoes
After 3 hours, add the celery root, parsley, celery leaves, and onions.
After 4 hours, add the tomatoes.
Thicken and finish
In a skillet, heat the browned flour and butter, then stir in a small ladle of the soup and cook until thickened.
Remove the soup meat, add the thickened mixture back to the soup, and season with salt and pepper.
Boil for a few more minutes until ready.
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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Celery + parsleytop 1% of all pairsSmell alikestrongCooked together6,810 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Parsley + peppertop 2% of all pairsSmell alikestrongCooked together34,122 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
Celery + tomatotop 4% of all pairsSmell alikemoderateCooked together3,377 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
Celery + peppertop 5% of all pairsSmell alikestrongCooked together16,012 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
Beef + oniontop 7% of all pairsSmell alikemoderateCooked together17,092 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
- Leg of beef
- Gives long-simmered meat flavour and body to the broth.
- Tomatoes
- Add acidity, colour and fresh tomato flavour to the soup.
- Browned flour
- Thickens the soup as it cooks with the butter.
- Celery root
- Adds a mild celery-like aroma and savoury depth to the broth.
- Onions
- Add savoury sweetness and aroma as they soften in the broth.
The step that matters
Thickening the flour and butter. Cooking the flour and butter together first lets the starch absorb liquid evenly. Adding it directly to the soup can cause lumps, so stir in a little hot soup before returning the mixture.
Swap the onion
How well each one fits the dish's main ingredients (beef, celery, parsley, tomato, flour, butter, pepper):
- Carrotfits better
- Okrafits better
- Capsicumfits better
- Onionthe original
Fit is the average pairing score against beef, celery, parsley, tomato, flour, butter, pepper. 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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