Why it works: Onion and potato 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 ↓
Mutton Soup
Ingredients
Directions
Prepare
Boil the leg of mutton and reserve the water for the soup.
Add the chopped onions, diced potato, barley, and chopped tomatoes to the water.
Season with pepper and coarse sea salt.
Cook the soup
Boil for one hour, stirring often to prevent the barley from burning.
Before removing from heat, mix the flour with cold water and add it to the soup.
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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Onion + potatotop 3% of all pairsSmell alikemoderateCooked together9,023 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Potato + tomatotop 5% of all pairsSmell alikestrongCooked together2,798 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Potato + barleytop 5% of all pairsSmell alikestrongCooked together165 recipes
Shared aroma: beta-damascenone (apple, rose).
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Tomato + peppertop 7% of all pairsSmell alikemoderateCooked together17,923 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + tomatotop 8% of all pairsSmell alikemoderateCooked together20,633 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
- Leg of mutton
- Gives the soup its meaty flavour and rich body as it boils.
- Barley
- Thickens the broth slightly and adds a chewy texture as it cooks.
- Potato
- Breaks down partly during cooking, adding body and starch to the broth.
- Flour
- Thickens the soup when stirred in with cold water before serving.
- Tomatoes
- Add acidity and a fresh, savoury sweetness to the broth.
The step that matters
Stirring the barley during the hour-long boil. Barley settles and sticks to the bottom of the pot, scorching easily. Regular stirring keeps it suspended and prevents a burnt taste.
Swap the tomato
How well each one fits the dish's main ingredients (mutton, onion, potato, barley, pepper, flour):
- Leekfits better
- Turnipfits better
- Chivefits better
- Tomatothe original
Fit is the average pairing score against mutton, onion, potato, barley, pepper, 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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