Name: Green Tomato Soy
Ingredients: 12 good-sized onions, sliced; 2 quarts vinegar; 1 quart sugar; 2 tablespoons salt; 2 tablespoons black pepper; 2 tablespoons ground mustard; 1 tablespoon allspice; 1 tablespoon cloves

Why it works: Allspice and clove match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 7,874 recipes. Both carry estragole, which smells anise, licorice. The science ↓

Green Tomato Soy

Ingredients

Directions

Combine all ingredients in a large pot.
Cook over medium heat until tender, stirring often.
Transfer to small glass jars for storage.

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.

Allspice + clovetop 1% of all pairs

Smell alikestrong

Cooked together7,874 recipes

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

Smell alikestrong

Cooked together1,928 recipes

Shared aroma: methyleugenol (clove, spice).
Pepper + clovetop 5% of all pairs

Smell alikestrong

Cooked together17,451 recipes

Shared aroma: ethyl octanoate (fruity, wine).
Pepper + allspicetop 5% of all pairs

Smell alikestrong

Cooked together6,395 recipes

Shared aroma: estragole (anise, licorice).
Onion + mustardtop 6% of all pairs

Smell alikestrong

Cooked together9,259 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).

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

Flavor stand-ins for the onion

How well each one fits the dish's main ingredients (vinegar, sugar, pepper, mustard, allspice, clove):

Horseradishbetter flavor fit
Capsicumbetter flavor fit
Shallotbetter flavor fit
Onionthe original

Fit is the average pairing score against vinegar, sugar, pepper, mustard, allspice, clove. Candidates are from the same food group and used in at least 100 recipes. This compares flavor only: it does not check the job the ingredient does in the dish (bulk, moisture, acidity, structure).