Name: Chicken Vegetable Soup
Ingredients: 1 fat hen; 1 gallon water; 3 or 4 Irish potatoes, sliced; 1 large onion, chopped; 1 to 2 tablespoons chopped parsley; 1 teaspoon celery seed; 1 red pepper pod; Salt to taste; 1 pint sweet milk

Why it works: Parsley and celery match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 6,810 recipes. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓

Chicken Vegetable Soup

Ingredients

Directions

Wash the hen and place it whole in a porcelain kettle with 1 gallon of water.
Boil for 2 hours.
After 1 hour, add the sliced potatoes, chopped onion, parsley, celery seed, red pepper pod, and salt.
When nearly done, stir in 1 pint of sweet milk.

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 + celerytop 1% of all pairs

Smell alikestrong

Cooked together6,810 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Parsley + peppertop 2% of all pairs

Smell alikestrong

Cooked together34,122 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).
Potato + oniontop 3% of all pairs

Smell alikemoderate

Cooked together9,023 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Potato + parsleytop 5% of all pairs

Smell alikemoderate

Cooked together2,855 recipes

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

Smell alikestrong

Cooked together16,012 recipes

Shared aroma: 4'-methylacetophenone (bitter almond).

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

What each ingredient does

Fat hen: Simmers into the broth, giving the soup its base flavor and body.
Irish potatoes: Soften during simmering, adding starch that thickens the broth slightly and gives body.
Sweet milk: Added near the end to enrich the broth with fat and a mild, creamy flavor.

Swap the onion

How well each one fits the dish's main ingredients (potato, parsley, celery, pepper, milk):

Carrotfits better
Capsicumfits better
Parsnipfits better
Onionthe original

Fit is the average pairing score against potato, parsley, celery, pepper, milk. 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.