Why it works: Pepper and parsley match in chemistry and in kitchens. They rank in the top 2% of all ingredient pairs, and cooks put them together in 34,122 recipes. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓
Cream of Potato Soup
Ingredients
Directions
Make the soup
In a pot, combine the milk and sliced onion with the bay leaf. Heat until just before boiling.
Remove the onion and bay leaf from the pot.
Add the mashed potatoes and stir until smooth.
Mix the flour with the butter or butter substitute, then add to the pot.
Cook until the soup thickens slightly.
Season and serve
Season with salt and pepper, then garnish with finely chopped parsley before serving.
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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Pepper + parsleytop 2% of all pairsSmell alikestrongCooked together34,122 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Potato + oniontop 3% of all pairsSmell alikemoderateCooked together9,023 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Potato + parsleytop 5% of all pairsSmell alikemoderateCooked together2,855 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
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Milk + buttertop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Onion + parsleytop 9% of all pairsSmell alikemoderateCooked together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Milk
- Forms the liquid base and gives the soup its creamy body.
- Mashed potatoes
- Add starch and body, helping the soup become thick and smooth.
- Flour
- Thickens the soup as its starch swells with heat.
- Butter
- Adds richness and a smooth, rounded flavour.
The step that matters
Adding the flour and butter mixture. Flour added directly to hot liquid can clump. Mixing it with butter first coats the starch grains so they disperse evenly, giving a smooth, lump-free thickening as the soup cooks.
Swap the onion
How well each one fits the dish's main ingredients (milk, flour, potato, butter, pepper, parsley):
- Carrotfits better
- Chivefits better
- Shallotfits better
- Onionthe original
Fit is the average pairing score against milk, flour, potato, butter, pepper, parsley. 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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