Name: Stock for Clear Soups
Ingredients: 4 onions; 1 gallon water; 1 carrot; 2 small turnips; 2 parsnips; 3 bay leaves; 1 head celery (or 1 teaspoon celery seeds); ⅛ head cabbage

Why it works: Turnip and parsnip match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 590 recipes. Both carry coumarin, which smells sweet, hay. The science ↓

Stock for Clear Soups

Ingredients

Directions

Place onions in a large kettle with water.
Boil steadily for 2 hours.
Add carrot, turnips, parsnips, bay leaves, celery, and cabbage.
Boil for 4 hours.
Strain the stock.

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.

Turnip + parsniptop 1% of all pairs

Smell alikestrong

Cooked together590 recipes

Shared aroma: coumarin (sweet, hay).
Carrot + parsniptop 1% of all pairs

Smell alikestrong

Cooked together1,097 recipes

Shared aroma: 2-isobutyl-3-methoxypyrazine (green bell pepper, earthy).
Carrot + celerytop 1% of all pairs

Smell alikestrong

Cooked together10,173 recipes

Shared aroma: myristicin (spice, warm).
Carrot + turniptop 1% of all pairs

Smell alikestrong

Cooked together8,002 recipes

Shared aroma: coumarin (sweet, hay).
Turnip + cabbagetop 2% of all pairs

Smell alikestrong

Cooked together897 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

Onions: Release sweetness and savory depth into the long-simmered liquid.
Carrot: Adds subtle sweetness and body to the stock.
Turnips: Contribute mild sweetness and earthy flavor to the broth.
Parsnips: Add sweetness and aromatic depth as they soften during simmering.
Celery: Adds a fresh, herbal aroma that rounds out the stock.
Cabbage: Contributes a light, slightly sweet vegetal note to the broth.

Swap the onion

How well each one fits the dish's main ingredients (carrot, turnip, parsnip, celery, cabbage):

Leekfits better
Beetrootfits better
Lettucefits better
Onionthe original

Fit is the average pairing score against carrot, turnip, parsnip, celery, cabbage. 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.