Why it works: Potato and onion are a kitchen classic. They rank in the top 3% of all ingredient pairs, and cooks put them together in 9,023 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
Potato Soup
Ingredients
Directions
Prepare
Peel and slice the potatoes and onion.
Make the soup
Boil them in 3 pints of water until tender.
Pulp the mixture through a colander.
Stir in the butter, cayenne pepper, and salt.
Finish and serve
Just before serving, add the cream and do not allow the soup to boil again.
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.
Photo for illustrative purposes only · Contact us to use it
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.
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Potato + oniontop 3% of all pairsSmell alikemoderateCooked together9,023 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Butter + creamtop 8% of all pairsSmell alikemoderateCooked together41,516 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
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Potato + peppertop 9% of all pairsSmell alikemoderateCooked together8,305 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Potato + buttertop 13% of all pairsSmell alikemoderateCooked together6,456 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Large mealy potatoes
- Break down when cooked and thicken the soup into a smooth body.
- Onion
- Adds savory flavor and aroma to the soup base.
- Butter
- Adds richness and a smooth, rounded mouthfeel.
- Heavy cream
- Adds richness and a silky texture when stirred in at the end.
The step that matters
Adding the cream off the boil. Cream can curdle or separate if it is boiled, so it should be stirred in just before serving and the soup kept below a boil.
Swap the onion
How well each one fits the dish's main ingredients (potato, butter, pepper, cream):
- Onionthe original
- Spinachfits about as well
- Chivefits about as well
- Capsicumfits about as well
Fit is the average pairing score against potato, butter, pepper, cream. 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.
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