Name: Horseradish Sauce
Ingredients: 1 onion; 1 teaspoon grated horseradish; 1-2 tablespoons essence of anchovies; butter; 1 tablespoon lemon-pickle or lemon-juice; optional: vinegar

Why it works: Onion and horseradish match in chemistry and in kitchens. They rank in the top 7% of all ingredient pairs, and cooks put them together in 1,784 recipes. Both carry coumarin, which smells sweet, hay. The science ↓

Horseradish Sauce

Ingredients

Directions

Stew the onion in a little fish stock until it becomes soft.
Add the grated horseradish and essence of anchovies, then mix well.
Thicken the sauce with a little butter.
Finish with lemon-pickle or lemon-juice, warming it gently.
If using vinegar, mix it with the horseradish and boil together.

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.

Onion + horseradishtop 7% of all pairs

Smell alikestrong

Cooked together1,784 recipes

Shared aroma: coumarin (sweet, hay).
Horseradish + lemontop 9% of all pairs

Smell alikestrong

Cooked together1,155 recipes

Shared aroma: coumarin (sweet, hay).
Horseradish + vinegartop 12% of all pairs

Smell alikemoderate

Cooked together2,609 recipes

Shared aroma: isobutyraldehyde (malty, green).
Onion + vinegartop 14% of all pairs

Smell alikemoderate

Cooked together18,226 recipes

Shared aroma: acetic acid (sour, vinegar).
Onion + buttertop 15% of all pairs

Smell alikemoderate

Cooked together42,912 recipes

Shared aroma: decanal (soap, orange peel).

Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs

Swap the lemon

How well each one fits the dish's main ingredients (onion, horseradish, butter, vinegar):

Avocadofits better
Plumfits about as well
Mangofits about as well
Lemonthe original

Fit is the average pairing score against onion, horseradish, butter, vinegar. Candidates are from the same food group and used in at least 100 recipes.