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
Cook the potatoes and onions until tender.
Rub them through a wire sieve with enough milk to achieve a creamy consistency.
Add the butter, pepper, and salt, then bring to a boil.
Finish and serve
If desired, stir in the whisked egg just 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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Milk + buttertop 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
- Their starch thickens the soup and gives it a smooth, body-rich texture when pureed.
- Onions
- They add savory sweetness and aroma as they soften during cooking.
- Milk
- It loosens the puree into a creamy consistency and adds richness.
- Egg
- When stirred in off the heat, it can add richness and a little extra body.
The step that matters
Rubbing through the sieve while the vegetables are hot. Starch in cooked potatoes sets as it cools and turns gluey or stiff, so passing them through the sieve while still hot gives a smoother, creamier result.
Swap the walnut
The recipe marks walnut as optional. How well each one fits the dish's main ingredients (potato, onion, milk, butter, pepper, egg):
- Beansfits better
- Peanutfits about as well
- Sesamefits about as well
- Walnutthe original
Fit is the average pairing score against potato, onion, milk, butter, pepper, egg. 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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