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 ↓
Pig's Liver and Bacon
Ingredients
Directions
Prepare
Slice the liver and soak it in cold water for 30 minutes to draw out the blood.
Wipe the liver dry, then season with salt, pepper, and flour.
Cook
Fry the bacon slices until crispy, then remove them from the pan.
In the same fat, cook the sliced onion until soft.
Strain the fat, return it to the pan, and heat until it hisses.
Add the floured liver slices and fry until browned.
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.
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Pepper + oniontop 11% of all pairsSmell alikemoderateCooked together68,474 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Liver + oniontop 15% of all pairsSmell alikelowCooked together1,420 recipes
Shared aroma: furaneol (caramel, strawberry).
-
Flour + oniontop 17% of all pairsSmell alikemoderateCooked together32,460 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Pepper + flourtop 19% of all pairsSmell alikemoderateCooked together50,459 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Liver + peppertop 21% of all pairsSmell alikemoderateCooked together2,375 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
- Pig's liver
- Is the main dish, cooked quickly so it browns outside while staying tender inside.
- Flour
- Coats the liver slices so they brown in the hot fat and form a light crust.
- Thin slices of fat bacon
- Renders fat for frying and leaves crisp pieces that add savoury flavour.
- Onion
- Softens and sweetens in the bacon fat, adding mild sweetness to the dish.
The step that matters
Heat the fat until it hisses before adding the liver. Hot fat sears the floured surface quickly, creating a browned crust that seals in moisture. Liver added to cool fat tends to steam, turn grey, and toughen.
Swap the onion
How well each one fits the dish's main ingredients (liver, pepper, flour):
- Shallotfits better
- Capsicumfits better
- Carrotfits better
- Onionthe original
Fit is the average pairing score against liver, pepper, flour. 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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