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 the potatoes
Peel the potatoes and boil them until tender.
Drain the water and mash the potatoes.
Make the soup
Add butter, milk, parsley, salt, and white pepper to the mashed potatoes and boil for a few minutes.
If using an onion, add it to the milk while heating, then remove it before serving.
If using parsley, place it in the serving bowl and pour the soup over it through a colander.
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 + parsleytop 5% of all pairsSmell alikemoderateCooked together2,855 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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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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Parsley + oniontop 9% of all pairsSmell alikemoderateCooked together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
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Potato + milktop 9% of all pairsSmell alikemoderateCooked together3,611 recipes
Shared aroma: (e,z)-2,6-nonadienal (cucumber, melon).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Potatoes
- Provide the starch and body that thicken the soup into a creamy texture when mashed.
- Butter
- Adds richness and a smooth mouthfeel to the soup.
- Milk
- Supplies the liquid that turns the mashed potato into a pourable soup.
The step that matters
Boil the soup after adding the milk. Boiling only a few minutes is enough to heat the dairy and blend the flavours without scorching. Boiling too hard or too long can scorch milk on the bottom of the pan and cause it to separate or taste cooked-down.
Swap the onion
The recipe marks onion as optional. How well each one fits the dish's main ingredients (potato, butter, milk, parsley, white pepper):
- Carrotfits better
- Chivefits better
- Shallotfits about as well
- Onionthe original
Fit is the average pairing score against potato, butter, milk, parsley, white 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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