Name: Biscotini Pistachios
Ingredients: 2 cups sugar; 2 cups flour; 8 oz. pistachios; 20 egg yolks

Why it works: Flour and pistachio match in chemistry and in kitchens. They rank in the top 7% of all ingredient pairs, and cooks put them together in 505 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓

Biscotini Pistachios

Oven, in the book's wordsA slack oven

Ingredients

2 cups sugar
2 cups flour
8 oz. pistachios
20 egg yolks

Directions

The book says “a slack oven”. The 350°F (175°C) in the steps is the modern equivalent, not the book's own figure.

Prepare the batter

In a bowl, mix the sugar and egg yolks well with a spatula.
Add the pistachios and flour to the mixture.
Pour the paste into two large baking pans, about 1 inch deep.

Bake and serve

Bake in a moderate oven at 350°F (175°C) until cooked through.
Once cooled, cut into slices like aniseed cakes.

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.

Flour + pistachiotop 7% of all pairs

Smell alikestrong

Cooked together505 recipes

Shared aroma: isobutyraldehyde (malty, green).
Sugar + flourtop 15% of all pairs

Smell alikemoderate

Cooked together92,116 recipes

Shared aroma: phenylacetaldehyde (hawthorne, honey).
Flour + eggtop 15% of all pairs

Smell alikelow

Cooked together106,462 recipes

Shared aroma: isobutyraldehyde (malty, green).
Sugar + eggtop 21% of all pairs

Smell alikemoderate

Cooked together122,807 recipes

Shared aroma: 2-nonenal (fatty, green).
Sugar + pistachiotop 21% of all pairs

Smell alikemoderate

Cooked together1,233 recipes

Shared aroma: 1-penten-3-one (fish, pungent).

Flour and egg barely smell alike, yet cooks put them together in 106,462 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

Egg yolks: Provide richness, moisture and structure as they set during baking.
Flour: Gives the cake its body and structure as it bakes.
Pistachios: Add nutty flavour and a fat-rich texture to the crumb.
Sugar: Sweetens the cake and helps it brown lightly in the oven.