Why it works: Beef and mushroom are a kitchen classic. They rank in the top 4% of all ingredient pairs, and cooks put them together in 3,232 recipes. Both carry 2,4-nonadienal, which smells fatty, green. The science ↓
Beef Kidney
Ingredients
Directions
Prepare the kidney
Trim and slice the kidney.
Season with salt and pepper, then dredge in flour.
Fry and make the gravy
Fry the slices on both sides until cooked through.
Remove the kidney from the pan and empty it.
In the same pan, melt butter and add 2 teaspoons of flour.
Stir in boiling water and simmer for 1 minute.
Add mushroom catsup, lemon juice, or vinegar for flavor.
Optionally, mix in minced herbs and finely chopped onion.
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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Beef + mushroomtop 4% of all pairsSmell alikemoderateCooked together3,232 recipes
Shared aroma: 2,4-nonadienal (fatty, green).
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Beef + oniontop 7% of all pairsSmell alikemoderateCooked together17,092 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
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Butter + mushroomtop 7% of all pairsSmell alikemoderateCooked together12,525 recipes
Shared aroma: trans-2-decenal (waxy, orange).
-
Beef + peppertop 10% of all pairsSmell alikemoderateCooked together18,971 recipes
Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
-
Mushroom + oniontop 10% of all pairsSmell alikemoderateCooked together10,626 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
- Beef kidney
- Is the main protein, cooked through by frying after being sliced.
- Flour
- Coats the slices so they brown, and thickens the gravy with the butter.
- Butter
- Fat that melts with the flour to start the gravy and adds richness.
- Boiling water
- Liquid that turns the butter and flour roux into a thin gravy.
The step that matters
Simmer the gravy after adding water. Simmering for a full minute cooks the raw flour taste out of the roux and lets the gravy thicken evenly, so it does not stay pasty or floury.
Swap the onion
The recipe marks onion as optional. How well each one fits the dish's main ingredients (beef, pepper, flour, butter, mushroom):
- Shallotfits better
- Chivefits about as well
- Potatofits about as well
- Onionthe original
Fit is the average pairing score against beef, pepper, flour, butter, mushroom. 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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