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 ↓
Irish Stew
Ingredients
Directions
The book says “a slack oven”. The 300°F (150°C) in the steps is the modern equivalent, not the book's own figure.
Prepare
Peel and boil the onions in water for 15 minutes, then discard the water.
Boil the peeled potatoes for 15 minutes, then discard this water.
Slice the boiled onions and potatoes into thick slices.
Cook the stew
In a saucepan, layer onions, potatoes, and mutton, seasoning with salt and pepper between layers.
Add 3¾ cups of cold water, cover tightly, and simmer on low heat for 3 hours. Alternatively, bake in a covered dish at 300°F (150°C) for the same time.
Serve the stew in one dish.
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 + peppertop 9% of all pairsSmell alikemoderateCooked together8,305 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
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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Onion + muttontop 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
- Thicken the stew as they break down and add body to the liquid.
- Onions
- Add sweetness and aroma as they soften during the long cooking.
The step that matters
Simmer gently over low heat. A low, gentle simmer keeps the mutton tender and prevents the liquid from boiling hard, which would toughen the meat and break up the potatoes.
Swap the onion
How well each one fits the dish's main ingredients (potato, mutton, pepper):
- Carrotfits better
- Capsicumfits better
- Tomatofits about as well
- Onionthe original
Fit is the average pairing score against potato, mutton, 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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