Why it works: Onion and potato 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 for Lent
Ingredients
Directions
Prepare
Slice and fry the onions in butter until browned.
Add the skim milk to the soup pot.
Peel and boil the potatoes until tender.
Make the soup
Mash the potatoes and gradually mix them into the milk until smooth.
Bring the soup to a boil and season with pepper and salt to taste.
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.
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Onion + potatotop 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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Milk + potatotop 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
- Onions
- Browned in butter, they add sweetness and deep savory flavor to the soup.
- Butter
- Frying the onions in it adds richness and browning flavor.
- Skim milk
- Forms the liquid base of the soup.
- Potatoes
- Mashed into the milk, they thicken the soup and give it body.
The step that matters
Mixing the mashed potatoes into the milk. Adding the potatoes gradually and stirring until smooth prevents lumps, since starch clumps when it is dispersed unevenly in liquid. Gradual addition helps the potato starch blend evenly and thicken the soup smoothly.
Swap the onion
How well each one fits the dish's main ingredients (butter, milk, potato, pepper):
- Capsicumfits better
- Asparagusfits about as well
- Tomatofits about as well
- Onionthe original
Fit is the average pairing score against butter, milk, potato, 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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