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
Mash the steamed or boiled potatoes until smooth.
Gradually mix in the boiling broth.
Pass the soup through a strainer and return it to the heat.
Add pepper and salt, and let it boil for five minutes.
Skim off any black scum that rises to the surface.
Finish and serve
If desired, sauté the minced onions until light brown, add to the soup, and stew for ten minutes before serving.
Serve hot with fried or toasted bread.
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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Potato + peppertop 9% of all pairsSmell alikemoderateCooked together8,305 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Pepper + oniontop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + breadtop 15% of all pairsSmell alikemoderateCooked together8,676 recipes
Shared aroma: 2,4-decadienal (seaweed).
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Potato + breadtop 15% of all pairsSmell alikemoderateCooked together434 recipes
Shared aroma: 2-acetyl-1-pyrroline (popcorn, roasted).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Mealy potatoes
- Their starch thickens the broth and gives the soup a smooth, body-rich texture when mashed.
- Broth
- Supplies the liquid base and most of the savoury flavour of the soup.
- Onions
- Add sweetness and aroma when sautéed until light brown before going into the soup.
The step that matters
Skim off the black scum. Scum rising to the surface can carry impurities and dark specks that cloud the soup's appearance and taste, so it should be removed before serving.
Swap the onion
The recipe marks onion as optional. How well each one fits the dish's main ingredients (potato, pepper, bread):
- Capsicumfits better
- Tomatofits better
- Carrotfits better
- Onionthe original
Fit is the average pairing score against potato, pepper, bread. 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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