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 the vegetables
Peel the onions.
Boil the peeled onions for 15 minutes.
Discard the water.
Boil the peeled potatoes for 15 minutes.
Discard the water.
Slice the boiled onions.
Cut the boiled potatoes into thick slices.
Cook the stew
In a saucepan, layer the onions, potatoes, and mutton, seasoning with salt and pepper between layers.
Add 3 cups of cold water.
Cover tightly.
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).
-
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
- Potatoes
- Break down during the long cooking to thicken the stew and give it body.
- Breast of mutton
- Becomes tender over the long, slow cooking, releasing flavour into the broth.
- Onions
- Parboiling softens them and adds sweetness to the broth as they cook.
The step that matters
Keeping the stew at a low, gentle simmer. Boiling hard toughens meat proteins and can break up the potatoes, while slow, gentle heat lets the collagen in the mutton soften into tender meat.
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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