Name: Chocolate Icing
Ingredients: 1 ⅔ cups sugar; 2 egg whites; 2 squares Baker's chocolate; ⅓ cup sugar; 4 tablespoons boiling water

Why it works: Sugar and chocolate are a kitchen classic. They rank in the top 13% of all ingredient pairs, and cooks put them together in 15,404 recipes. Both carry guaiacol, which smells smoky, sweet. The science ↓

Chocolate Icing

enough to ice two sheets of cake

Oven, in the book's wordsA quick oven

Ingredients

Directions

Beat 1 ⅔ cups of sugar into the unbeaten egg whites.
In a small frying pan, combine 2 squares of Baker's chocolate, ⅓ cup of sugar, and 4 tablespoons of boiling water, then stir over high heat until the mixture is smooth and glossy.
Stir the chocolate mixture into the beaten egg whites and sugar.

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.

Sugar + chocolatetop 13% of all pairs

Smell alikemoderate

Cooked together15,404 recipes

Shared aroma: guaiacol (smoky, sweet).
Sugar + eggtop 21% of all pairs

Smell alikemoderate

Cooked together122,807 recipes

Shared aroma: 2-nonenal (fatty, green).
Egg + chocolatetop 24% of all pairs

Smell alikemoderate

Cooked together11,448 recipes

Shared aroma: 2-heptenal (green).

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

What each ingredient does

Egg whites: Whipped with sugar to create a light, airy foam that gives the icing its body.
Baker's chocolate: Provides the chocolate flavour and colour of the icing.
Sugar: Sweetens the icing and helps stabilise the whipped egg whites.

“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.