Name: Mackerel Roe, Sauce of
Ingredients: 2 or 3 mackerel roes; 2 hard-boiled egg yolks; fennel sauce or parsley and butter; 1 tablespoon walnut ketchup; pepper to taste; coarse sea salt to taste; vinegar to taste

Why it works: Fennel and pepper match in chemistry and in kitchens. They rank in the top 7% of all ingredient pairs, and cooks put them together in 1,216 recipes. Both carry myristicin, which smells spice, warm. The science ↓

Mackerel Roe, Sauce of

Ingredients

Directions

Prepare

Boil the mackerel roes in water for 10 minutes.
Pound the boiled roes with the yolks of the hard-boiled eggs.
Prepare fennel sauce or parsley and butter.

Finish the sauce

Stir the pounded roes and egg yolks into the sauce.
Add walnut ketchup, pepper, salt, and vinegar as needed.

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.

Fennel + peppertop 7% of all pairs

Smell alikestrong

Cooked together1,216 recipes

Shared aroma: myristicin (spice, warm).
Fennel + walnuttop 9% of all pairs

Smell alikestrong

Cooked together74 recipes

Shared aroma: eucalyptol (eucalyptus, herbal).
Roe + ketchuptop 12% of all pairs

Smell alikemoderate

Cooked together21 recipes

Shared aroma: ethanol (alcoholic, ethereal).
Walnut + peppertop 13% of all pairs

Smell alikemoderate

Cooked together3,039 recipes

Shared aroma: 2-nonenal (fatty, green).
Roe + eggtop 14% of all pairs

Smell alikemoderate

Cooked together243 recipes

Shared aroma: (e)-2-octenal (fatty, green).

Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs

What each ingredient does

Mackerel roes: Provide the rich, creamy body that thickens and flavours the sauce.
Hard-boiled egg yolks: Bind with the pounded roes to give a smooth, thick texture.
Walnut ketchup: Adds a savoury, slightly tangy depth of flavour.

Swap the fennel

How well each one fits the dish's main ingredients (roe, egg, walnut, ketchup, pepper, vinegar):

Tarragonfits better
Parsleyfits better
Allspicefits better
Fennelthe original

Fit is the average pairing score against roe, egg, walnut, ketchup, pepper, vinegar. 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.