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 ↓
Irish Potato Soup
Ingredients
Directions
Make the soup
Peel and boil the potatoes with the sliced onion, herbs, salt, and pepper.
Press the mixture through a colander.
Thin the soup with rich milk.
Add a lump of butter.
Adjust seasoning if necessary.
Heat well.
Serve
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.
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).
-
Milk + buttertop 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
- Starch that breaks down and thickens the soup into a smooth, creamy body.
- Rich milk
- Adds moisture and creaminess, thinning the purée to a silky texture.
- Butter
- Adds fat and richness, rounding out the flavour and mouthfeel.
- Onion
- Contributes savoury aroma and sweetness as it cooks into the broth.
The step that matters
Press the mixture through a colander. Pressing the cooked potatoes and onion breaks down their cell walls into a smooth purée. Leaving lumps or skipping this step gives a grainy, uneven texture instead of a silky soup.
Swap the onion
How well each one fits the dish's main ingredients (potato, pepper, milk, butter):
- Capsicumfits better
- Asparagusfits about as well
- Tomatofits about as well
- Onionthe original
Fit is the average pairing score against potato, pepper, milk, butter. 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.
You might also like
The 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.
Potato Croquettes255 recipes
Potato Rolls78 recipes
Potato Chips53 recipes
Sweet Potato Croquettes53 recipes