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
Wash the potatoes well in cold water.
Peel the potatoes, remove any eyes or black specks, and slice them.
Peel the onions and slice them.
Wash the mutton in cold water, scrape it clean, and trim off the fat.
Cut the mutton into small pieces.
Layer and cook
In a large saucepan, layer the meat, then potatoes, then onions.
Sprinkle a little pepper and coarse sea salt over each layer.
Continue layering until all meat and vegetables are used.
Pour in enough cold water to cover the bottom of the saucepan (about ½ pint).
Place the saucepan on the fire and bring to a boil, then skim the surface.
Reduce heat and let it stew gently for 1.5 to 2 hours, skimming and stirring occasionally.
Serve
Serve the stew hot on a 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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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).
-
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).
-
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
- Potatoes
- Bulk up the stew and thicken the liquid as their starch softens during slow cooking.
- Scrag end of mutton
- Provides the meat and rich flavour as its connective tissue breaks down during long, gentle stewing.
- Onions
- Add sweetness and aroma that deepen as they cook slowly in the broth.
The step that matters
Reduce heat and stew gently. Boiling hard toughens the mutton and can break up the potatoes, while a gentle simmer lets the connective tissue soften into tender meat and keeps the stew clear.
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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