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 Stew
Ingredients
Directions
Prepare
Trim excess fat from the mutton and cut it into moderate thickness chops.
Peel and halve the potatoes, and slice the onions thickly.
Layer and stew
Layer potatoes at the bottom of a stewpan, followed by mutton and onions, seasoning with pepper and salt.
Repeat layers until the stewpan is full, ensuring plenty of vegetables on top.
Pour in the water and let it stew gently for 24 hours with the lid tightly closed, shaking occasionally to prevent burning.
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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Potato + oniontop 3% of all pairsSmell alikemoderateCooked together9,023 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Potato + peppertop 9% of all pairsSmell alikemoderateCooked together8,305 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Onion + peppertop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Mutton + peppertop 16% of all pairsSmell alikelowCooked together5,442 recipes
Shared aroma: trans-2-nonenal (cardboard, fatty).
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Mutton + oniontop 18% of all pairsSmell alikelowCooked together4,531 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
- Mutton
- Provides the meat and rich flavour that the stew is built around.
- Potatoes
- Form the base layer and thicken the stew as they break down during slow cooking.
- Onions
- Add sweetness and aromatic depth as they soften during the long stew.
The step that matters
Stewing gently with the lid closed. Gentle, covered heat keeps the meat tender and the liquid from evaporating, while occasional shaking stops the bottom layer from scorching. Too much heat would toughen the meat and burn the potatoes.
Swap the onion
How well each one fits the dish's main ingredients (mutton, potato, pepper):
- Carrotfits better
- Capsicumfits better
- Tomatofits about as well
- Onionthe original
Fit is the average pairing score against mutton, potato, 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.
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