Why it works: Ketchup and sauce match in chemistry and in kitchens. They rank in the top 1% of all ingredient pairs, and cooks put them together in 1,099 recipes. Both carry ethanol, which smells alcoholic, ethereal. The science ↓
Kidneys on Toast
Ingredients
Directions
Make the sauce
Fry the kidneys in the butter until cooked.
Chop the cooked kidneys finely.
Mix the flour into the butter.
Add the stock and sauces.
Bring the mixture to a boil.
Skim the mixture well.
Finish and serve
Add the chopped kidneys.
Cook slowly for twenty minutes.
Serve on hot buttered toast, garnished with rolls of bacon and fried bread dipped in chopped parsley and grated cheese.
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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Ketchup + saucetop 1% of all pairsSmell alikestrongCooked together1,099 recipes
Shared aroma: ethanol (alcoholic, ethereal).
-
Butter + breadtop 7% of all pairsSmell alikemoderateCooked together27,232 recipes
Shared aroma: delta-decalactone (sweet, creamy).
-
Butter + mushroomtop 7% of all pairsSmell alikemoderateCooked together12,525 recipes
Shared aroma: trans-2-decenal (waxy, orange).
-
Bread + cheesetop 7% of all pairsSmell alikemoderateCooked together2,130 recipes
Shared aroma: delta-decalactone (sweet, creamy).
-
Butter + cheesetop 8% of all pairsSmell alikemoderateCooked together7,962 recipes
Shared aroma: delta-dodecalactone (sweet, creamy).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Sheep's kidneys
- Provide the main meat, which becomes tender with slow cooking in the sauce.
- Butter
- Carries the frying of the kidneys and enriches the base of the sauce with fat and flavour.
- Flour
- Mixed into the butter to form a roux that thickens the stock into a smooth sauce.
- Stock
- Forms the liquid base of the sauce, adding savoury depth and moisture.
- Mushroom ketchup
- Adds concentrated savoury, umami flavour to the sauce.
The step that matters
Mix the flour into the butter. The flour must be cooked with the fat to form a roux before liquid is added; otherwise the sauce may stay floury or form lumps.
Swap the parsley
How well each one fits the dish's main ingredients (butter, flour, mushroom, ketchup, sauce, bread, cheese):
- Capersfits better
- Thymefits about as well
- Nutmegfits about as well
- Parsleythe original
Fit is the average pairing score against butter, flour, mushroom, ketchup, sauce, bread, cheese. 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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