Name: Fish Salads
Ingredients: 2 egg yolks; ½ teaspoon coarse sea salt; ¼ teaspoon black pepper; ½ teaspoon sugar; ½ teaspoon finely chopped onions; ½ teaspoon finely chopped parsley; ½ teaspoon tarragon or chervil; oil; vinegar

Why it works: Parsley and tarragon match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 1,563 recipes. Both carry estragole, which smells anise, licorice. The science ↓

Fish Salads

Ingredients

Directions

In a medium bowl, combine the egg yolks, salt, pepper, sugar, onions, and parsley.
Slowly drizzle in oil while stirring with a wooden spoon until the mixture thickens.
Gradually add vinegar until the desired flavor is achieved.
Taste and adjust seasoning as needed.
Make in a cool place, especially in summer.

Recipe from a historical cookbook (Internet Archive).

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.

Parsley + tarragontop 1% of all pairs

Smell alikestrong

Cooked together1,563 recipes

Shared aroma: estragole (anise, licorice).
Pepper + parsleytop 2% of all pairs

Smell alikestrong

Cooked together34,122 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Pepper + tarragontop 5% of all pairs

Smell alikestrong

Cooked together2,399 recipes

Shared aroma: estragole (anise, licorice).
Tarragon + vinegartop 7% of all pairs

Smell alikemoderate

Cooked together2,547 recipes

Shared aroma: isobutyraldehyde (malty, green).
Onion + parsleytop 9% of all pairs

Smell alikemoderate

Cooked 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

Swap the onion

How well each one fits the dish's main ingredients (egg, pepper, sugar, parsley, tarragon, vinegar):

Shallotfits better
Mustardfits better
Capsicumfits better
Onionthe original

Fit is the average pairing score against egg, pepper, sugar, parsley, tarragon, vinegar. Candidates are from the same food group and used in at least 100 recipes.