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
Make the soup
Melt the butter or dripping in a three-quart saucepan.
Add the onions and cook for 5 minutes, stirring occasionally.
Add the potatoes and water (or milk and water) to the saucepan.
Cook until the potatoes and onions are soft.
Strain and finish
Strain the mixture through a fine sieve back into the saucepan.
Pass the vegetables through the sieve to create a puree and stir it into the soup.
Season with pepper and coarse sea salt.
For a richer flavor, add milk or cream before serving.
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 + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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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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Potato + milktop 9% of all pairsSmell alikemoderateCooked together3,611 recipes
Shared aroma: (e,z)-2,6-nonadienal (cucumber, melon).
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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 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
What each ingredient does
- Potatoes
- Break down when cooked to give the soup its body and thick texture.
- Onions
- Soften and sweeten as they cook, adding savory depth to the soup.
- Butter or sweet beef dripping
- Carries the flavor of the onions and adds richness to the soup.
- Milk or cream
- Adds richness and a smoother, creamier mouthfeel when stirred in.
The step that matters
Strain the mixture through a fine sieve. Pushing the soft potatoes and onions through a fine sieve breaks them into a smooth puree. Leaving lumps or skipping the straining step gives the soup a coarse, grainy texture.
Swap the onion
How well each one fits the dish's main ingredients (potato, butter, milk, pepper):
- Capsicumfits better
- Asparagusfits about as well
- Tomatofits about as well
- Onionthe original
Fit is the average pairing score against potato, butter, milk, pepper. 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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