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 ↓
Rice and Onion Soup
Ingredients
Directions
Prepare
Chop the onions very finely.
Make the soup
In a pot, fry the onions in butter until slightly browned.
Add the rice, seasoning, and water.
Cook gently until the rice is quite soft.
Serve
If desired, stir in the chopped parsley before serving.
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.
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).
-
Onion + parsleytop 9% of all pairsSmell alikemoderateCooked together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
-
Onion + ricetop 9% of all pairsSmell alikemoderateCooked together10,433 recipes
Shared aroma: 2,4-decadienal (seaweed).
-
Rice + parsleytop 10% of all pairsSmell alikestrongCooked together2,762 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 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
- Onions
- Fried in butter until browned, they add sweetness and savory depth to the broth.
- Rice
- Softens during gentle cooking, thickening the soup and giving it body.
- Butter
- Fat that carries the onion flavor and helps the onions brown.
The step that matters
Cook gently until the rice is quite soft. Simmering gently rather than boiling hard lets the rice soften evenly and release starch slowly, so the soup thickens smoothly without the rice breaking down into a gluey mass.
Swap the parsley
The recipe marks parsley as optional. How well each one fits the dish's main ingredients (onion, rice, butter, pepper):
- Parsleythe original
- Garlicfits about as well
- Turmericfits about as well
- Thymefits about as well
Fit is the average pairing score against onion, rice, 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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