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 ↓
Economical Soup
Ingredients
Directions
Make the broth
In a kettle, combine bits of beef or mutton and broken bones.
Add 2 nice Irish potatoes, 4 pints of cold water, and 2 small onions, finely chopped.
Stir in 2 teaspoons of rice.
Boil for 1½ hours.
Strain the mixture and return to the kettle.
Finish and serve
Add 1½ pints of milk and a lump of butter.
Stir in 1 tablespoon of flour until smooth.
Season with salt, pepper, and finely chopped celery.
Serve with small squares of bread or crackers fried brown in butter.
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.
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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 + ricetop 7% of all pairsSmell alikestrongCooked together851 recipes
Shared aroma: 2-acetyl-1-pyrroline (popcorn, roasted).
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Beef + oniontop 7% of all pairsSmell alikemoderateCooked together17,092 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).
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Rice + milktop 7% of all pairsSmell alikemoderateCooked together7,374 recipes
Shared aroma: 2-nonenal (fatty, green).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Beef or mutton bones
- Release gelatin and savory flavour into the broth as they simmer.
- Milk
- Adds creaminess and mild sweetness, softening the broth's savoury edge.
- Flour
- Thickens the liquid so the soup becomes smooth and lightly body-rich.
- Potatoes
- Break down slightly during boiling, adding starch that gives body to the soup.
- Rice
- Adds starch as it cooks, contributing further body to the soup.
The step that matters
Stirring in the flour until smooth. Flour clumps if added to hot liquid without being mixed well first. Whisking it smooth, ideally into a little cold liquid before adding, lets its starch thicken the soup evenly.
Swap the onion
How well each one fits the dish's main ingredients (beef, potato, rice, milk, egg, butter, flour):
- Asparagusfits better
- Chivefits better
- Leekfits better
- Onionthe original
Fit is the average pairing score against beef, potato, rice, milk, egg, butter, flour. 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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