Why it works: Parsley and pepper 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 ↓
Spring Vegetable Soup
Ingredients
Directions
Make the soup base
Combine the lettuces, onion, parsley, butter, and water in a stewpan.
Simmer until tender.
Season with salt and pepper.
Strain off the vegetables and mix two-thirds of the liquid with the soup stock.
Finish and serve
Beat the egg yolks with the remaining third of the liquid.
Heat gently, then add the egg mixture and vegetables to the strained soup just 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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Parsley + peppertop 2% of all pairsSmell alikestrongCooked together34,122 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Lettuce + parsleytop 5% of all pairsSmell alikestrongCooked together1,483 recipes
Shared aroma: trans-2-hexenal (green, leafy).
-
Peas + lettucetop 5% of all pairsSmell alikestrongCooked together1,293 recipes
Shared aroma: 2-isobutyl-3-methoxypyrazine (green bell pepper, earthy).
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Lettuce + oniontop 8% of all pairsSmell alikestrongCooked together3,562 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + parsleytop 9% of all pairsSmell alikemoderateCooked together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Lettuces
- Softens into the broth, adding body and a mild vegetal flavour.
- Butter
- Adds richness and carries flavour through the simmered vegetables.
- Egg yolks
- Thicken the soup gently and give it a silky, enriched texture when heated.
- Soup stock
- Forms the main liquid base, providing savoury depth to the soup.
The step that matters
Heat gently after adding the egg mixture. Egg yolks thicken through gentle heat. If the soup boils after they are added, the yolks can scramble and curdle, leaving a grainy texture instead of a smooth, silky one.
Swap the onion
How well each one fits the dish's main ingredients (peas, lettuce, parsley, butter, egg, pepper):
- Shallotfits better
- Spinachfits better
- Asparagusfits better
- Onionthe original
Fit is the average pairing score against peas, lettuce, parsley, butter, egg, 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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