Name: Lamb Kidneys a LA Terrapin
Ingredients: 6 lamb kidneys; 1 tablespoon butter; 1 tablespoon flour; 1 teacup milk; 1 hard-boiled egg, chopped fine; ½ teaspoon coarse sea salt; ¼ teaspoon white pepper; 2 teaspoons minced parsley

Why it works: Butter and milk are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 81,283 recipes. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓

Lamb Kidneys a LA Terrapin

Ingredients

Directions

Prepare the kidneys

Cut the lamb kidneys in halves.
Soak the kidneys in cold water and boil for about 15 minutes.

Make the sauce

In a saucepan, melt butter and mix with flour, then gradually add milk to make a white sauce.
Cut the kidneys into smaller pieces and add to the sauce with the chopped egg, salt, pepper, and parsley.
Cook in the hot sauce for 2 minutes.

Recipe from a historical cookbook (Internet Archive).

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.

Butter + milktop 7% of all pairs

Smell alikemoderate

Cooked together81,283 recipes

Shared aroma: (z)-4-heptenal (biscuit, cream).
Lamb + parsleytop 11% of all pairs

Smell alikemoderate

Cooked together1,322 recipes

Shared aroma: 2,4-decadienal (seaweed).
Butter + flourtop 12% of all pairs

Smell alikelow

Cooked together124,287 recipes

Shared aroma: isobutyraldehyde (malty, green).
Flour + parsleytop 12% of all pairs

Smell alikemoderate

Cooked together16,675 recipes

Shared aroma: isobutyraldehyde (malty, green).
White pepper + parsleytop 14% of all pairs

Smell alikelow

Cooked together1,451 recipes

Shared aroma: myrcene (balsamic, herbaceous).

Butter and flour 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

Lamb kidneys: Provide the meaty main substance and texture of the dish.
Butter: Adds richness and fat, and helps form the base of the sauce with flour.
Flour: Thickens the butter and milk into a white sauce by gelatinizing with the liquid.
Milk: Forms the liquid of the white sauce, giving it a smooth, creamy body.
Hard-boiled egg: Adds richness and a soft, firm texture to the sauce.

The step that matters

Adding the kidneys to the sauce and cooking briefly. Kidneys become tough and rubbery if overcooked. Since they were already boiled, the short 2-minute cook in the hot sauce only needs to heat them through without prolonged simmering.

Swap the white pepper

How well each one fits the dish's main ingredients (lamb, butter, flour, milk, egg, parsley):

Nutmegfits better
Cinnamonfits better
Capersfits better
White pepperthe original

Fit is the average pairing score against lamb, butter, flour, milk, egg, parsley. 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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Lamb Kidneys a LA Terrapin