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
Wash and peel the potatoes, then cut them into half-inch pieces.
Chop the onions finely.
Make the soup
Melt the butter in a saucepan.
Add the potatoes and onions, cooking for a few minutes without browning.
Add 1 pint of boiling water (or cold if time allows), along with pepper and salt.
Boil until the vegetables are soft.
Use a wire sieve or colander to strain the vegetables, pressing them through with a wooden spoon.
Return the strained soup to the saucepan.
Add the milk and bring to a boil.
Once boiling, gradually sprinkle in the tapioca while stirring continuously.
Let it boil gently for seven minutes.
Serve
Serve the soup in a hot tureen.
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.
-
Potato + oniontop 3% of all pairsSmell alikemoderateCooked together9,023 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Butter + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
-
Potato + peppertop 9% of all pairsSmell alikemoderateCooked together8,305 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Potato + milktop 9% of all pairsSmell alikemoderateCooked together3,611 recipes
Shared aroma: (e,z)-2,6-nonadienal (cucumber, melon).
-
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
- Break down when boiled and pressed to give the soup its body and thickness.
- Tapioca
- Thickens the liquid as its starch swells on boiling, giving a smoother texture.
- Milk
- Adds creaminess and richness to the soup's flavour and mouthfeel.
- Butter
- Fat that carries flavour from the onions and enriches the soup.
- Onions
- Contribute aroma and savoury flavour as they soften in the butter.
The step that matters
Sprinkle in the tapioca gradually while stirring. Tapioca added in one go clumps into lumps that do not dissolve evenly. Sprinkling it slowly into boiling liquid while stirring disperses the granules so their starch thickens the soup smoothly.
Swap the onion
How well each one fits the dish's main ingredients (potato, butter, milk, pepper):
- Capsicumfits better
- Asparagusfits about as well
- Tomatofits about as well
- Onionthe original
Fit is the average pairing score against potato, butter, milk, 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.
More potato soup recipes
You might also like
Potato Croquettes255 recipes
Potato Rolls78 recipes
Potato Chips53 recipes
Sweet Potato Croquettes53 recipesThe free Flavor Lab newsletter: one surprising pairing a week and the molecular reason it works, in 60 seconds. No spam, unsubscribe anytime.
Prefer an account? Create a free account to save pairings and unlock the full chemistry.