Why it works: Butter and mushroom are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 12,525 recipes. Both carry trans-2-decenal, which smells waxy, orange. The science ↓
Beef Kidney
Ingredients
Directions
Prepare
Cut the kidney into thin slices.
Flour the slices.
Fry and make the gravy
Fry the slices until nicely browned.
Remove excess fat from the pan and add butter.
Pour in boiling water.
Season with pepper, coarse sea salt, and mushroom ketchup.
Let the gravy boil briefly.
Serve
Pour the gravy over the kidney.
Serve.
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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Butter + mushroomtop 7% of all pairsSmell alikemoderateCooked together12,525 recipes
Shared aroma: trans-2-decenal (waxy, orange).
-
Pepper + mushroomtop 11% of all pairsSmell alikemoderateCooked together13,580 recipes
Shared aroma: 2-nonenal (fatty, green).
-
Flour + buttertop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + ketchuptop 13% of all pairsSmell alikemoderateCooked together2,435 recipes
Shared aroma: ethanol (alcoholic, ethereal).
-
Mushroom + ketchuptop 16% of all pairsSmell alikelowCooked together2,225 recipes
Shared aroma: ethanol (alcoholic, ethereal).
Flour and butter barely smell alike, yet cooks put them together in 124,287 recipes: they work on texture and structure more than aroma.
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Kidney
- Forms the main meat, which is cut thin so it cooks through quickly and stays tender.
- Flour
- Coats the slices so they brown well and help thicken the gravy.
- Butter
- Adds richness and fat for flavour once the pan fat is removed.
- Mushroom ketchup
- Adds savoury, umami depth to the gravy.
The step that matters
Fry the slices until nicely browned. Browning through high heat creates savoury flavour compounds, while overcrowding or too little heat makes the slices steam and turn grey and tough. Dry, floured slices brown best.
“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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