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 ↓
Onion Omelet
Ingredients
Directions
Prepare
Beat the eggs in a bowl and season with salt and pepper.
Cook
Heat a non-stick skillet over medium heat and pour in the eggs.
Cook until the edges start to set, then sprinkle the chopped onion and minced parsley on top.
Fold the omelet in half and cook for another minute until fully set.
Serve
Serve immediately.
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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Onion + parsleytop 9% of all pairsSmell alikemoderateCooked together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
-
Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Egg + parsleytop 21% of all pairsSmell alikemoderateCooked together18,765 recipes
Shared aroma: 2,4-decadienal (seaweed).
-
Egg + peppertop 33% of all pairsSmell alikelowCooked together50,580 recipes
Shared aroma: 2-nonenal (fatty, green).
Egg and pepper barely smell alike, yet cooks put them together in 50,580 recipes: they work on texture and structure more than aroma.
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Eggs
- Set into a tender structure that forms the body of the omelet.
- Onion
- Adds a sharp, savoury flavour that mellows slightly as it cooks.
- Parsley
- Adds fresh, green aroma and a light herbal note.
The step that matters
Cook until the edges start to set, then fold. Eggs set quickly with heat. Pulling the edges too late can overcook the base and make it rubbery, while folding too early leaves the centre runny and hard to fold cleanly.
Swap the onion
How well each one fits the dish's main ingredients (egg, parsley, pepper):
- Carrotfits better
- Capsicumfits better
- Spinachfits better
- Onionthe original
Fit is the average pairing score against egg, parsley, 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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