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 ↓
Cream of Lettuce Soup
Ingredients
Directions
Make the soup
Cook the shredded lettuce in the stock for 30 minutes.
Rub the mixture through a colander and return it to the heat.
Stir in the white roux, minced onion, and parsley.
Finish and serve
In a separate vessel, heat the milk and season with pepper and salt, then stir in the whipped egg.
Pour this mixture into a tureen, add the lettuce soup to the tureen, and serve with dinner biscuits.
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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Parsley + peppertop 2% of all pairsSmell alikestrongCooked together34,122 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Lettuce + biscuittop 4% of all pairsSmell alikestrongCooked together42 recipes
Shared aroma: nonanal (fat, citrus).
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Lettuce + parsleytop 5% of all pairsSmell alikestrongCooked together1,483 recipes
Shared aroma: trans-2-hexenal (green, leafy).
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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 + biscuittop 8% of all pairsSmell alikemoderateCooked together428 recipes
Shared aroma: coumarin (sweet, hay).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Lettuce
- Provides the main body and green flavour of the soup once cooked and pressed through.
- White roux
- Thickens the soup as the starch cooks and swells in the hot liquid.
- Egg
- Enriches and thickens the milk mixture, giving it a smoother, richer texture.
- Milk
- Adds creaminess and mild sweetness, softening the savoury flavour of the stock.
The step that matters
Adding the whipped egg. Egg thickens by setting when heated. If the milk mixture is too hot or the egg is added too quickly, it can curdle or turn grainy instead of silky.
Swap the onion
How well each one fits the dish's main ingredients (lettuce, parsley, milk, pepper, egg, biscuit):
- Spinachfits better
- Chivefits better
- Beetrootfits better
- Onionthe original
Fit is the average pairing score against lettuce, parsley, milk, pepper, egg, biscuit. 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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