Why it works: Pepper and onion are a kitchen classic. They rank in the top 11% of all ingredient pairs, and cooks put them together in 68,474 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓
To Roast Ducks
Ingredients
Directions
Prepare
Wash the ducks and rub them with coarse sea salt and black pepper.
Toast the bread for the filling and crush it with a rolling pin.
Season the crushed bread with black pepper, coarse sea salt, and chopped onion.
Roast and serve
Place the ducks in a pan and roast for 3 hours.
Optionally, roast 3-4 onions with the ducks.
Serve the onions on the 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.
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.
-
Pepper + oniontop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Bread + oniontop 15% of all pairsSmell alikemoderateCooked together8,676 recipes
Shared aroma: 2,4-decadienal (seaweed).
-
Pepper + breadtop 16% of all pairsSmell alikemoderateCooked together20,964 recipes
Shared aroma: 2-nonenal (fatty, green).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Ducks
- Provide the main meat, which becomes tender and juicy during long roasting.
- Bread
- Forms the base of the filling and soaks up flavour and moisture.
- Onions
- Add sweetness and aroma as they roast alongside the ducks.
Swap the onion
The recipe marks onion as optional. How well each one fits the dish's main ingredients (pepper, bread):
- Capsicumfits better
- Tomatofits better
- Spinachfits better
- Onionthe original
Fit is the average pairing score against pepper, bread. 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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