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
Cut the mutton into chops of moderate thickness.
Pare and slice the potatoes, and cut the onions into rings.
Layer and stew
Put a layer of potatoes at the bottom of a stewing pan.
Add a layer of mutton and onions, seasoning with pepper and salt.
Repeat layers until all ingredients are used, ensuring plenty of vegetables are on top.
Pour in the water and let it stew gently for 2.5 hours with the lid tightly closed.
Occasionally shake the pot 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 layers and thicken the stew as their starch softens during cooking.
- Onions
- Add sweetness and aroma as they soften slowly in the stewing liquid.
- Water
- Creates the stewing liquid that gently cooks the layers and turns them tender.
The step that matters
Pour in the water and let it stew gently for 2.5 hours with the lid tightly closed.. Gentle, covered simmering keeps the meat tender and the potatoes intact. Boiling hard or lifting the lid lets liquid escape and can toughen the meat and break up 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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