Why it works: Potato and leek work together. They rank in the top 6% of all ingredient pairs, and cooks put them together in 30 recipes. Both carry 1-octen-3-ol, which smells mushroom, earthy. The science ↓
Potato Soup
Ingredients
Directions
Prepare
Boil the water in a saucepan.
Cut the vegetables into very small pieces.
If using leeks, cut off the green tops, peel, wash, and slice them.
Make the soup
Add the vegetables, butter, salt, and pepper to the boiling water.
Simmer gently for about 1 hour, or until the vegetables are soft.
Rub the soup through a sieve or colander with a wooden spoon.
Finish and serve
Pour the soup back into the saucepan, add the milk and thickening, and let it boil for about 15 minutes, stirring frequently.
Serve hot.
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 + leektop 6% of all pairsSmell alikemoderateCooked together30 recipes
Shared aroma: 1-octen-3-ol (mushroom, earthy).
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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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Leek + semolinatop 11% of all pairsSmell alikestrongCooked together4 recipes
Shared aroma: 1-octen-3-ol (mushroom, earthy).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Potatoes
- Break down during simmering to give the soup body and a smooth, thick texture.
- Leeks or onions
- Soften and release sweet, savoury flavour into the broth as they simmer.
- Butter or clarified dripping
- Adds fat, carrying flavour and giving the soup a rich mouthfeel.
- Milk
- Adds creaminess and softness, mellowing the soup's flavour when it boils.
- Semolina, hominy, or sago
- Thickens the soup as its starch swells during the final boil.
The step that matters
Boiling the soup with the milk and thickening. Once milk and starch are added, the soup can scorch or stick to the base, and the thickener needs a full boil to swell and thicken properly. Stirring often prevents burning and lumps.
Swap the leek
How well each one fits the dish's main ingredients (potato, butter, milk, semolina, pepper):
- Capsicumfits about as well
- Chivefits about as well
- Spinachfits about as well
- Leekthe original
Fit is the average pairing score against potato, butter, milk, semolina, 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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