Name: Confectioners' Frosting
Ingredients: 2 tablespoons boiling water or boiling fruit juice; 1 teaspoon lemon juice; confectioners' sugar (enough to spread)

Why it works: Sugar and spread match in chemistry and in kitchens. They rank in the top 10% of all ingredient pairs, and cooks put them together in 260 recipes. Both carry ethanol, which smells alcoholic, ethereal. The science ↓

Confectioners' Frosting

Ingredients

2 tablespoons boiling water or boiling fruit juice
1 teaspoon lemon juice
confectioners' sugar (enough to spread)

Directions

Combine the boiling water or fruit juice with the lemon juice.
Gradually add confectioners' sugar until the mixture is thick enough to spread.

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 + spreadtop 10% of all pairs

Smell alikestrong

Cooked together260 recipes

Shared aroma: ethanol (alcoholic, ethereal).
Lemon + sugartop 18% of all pairs

Smell alikelow

Cooked together53,532 recipes

Shared aroma: 2-nonenal (fatty, green).
Lemon + spreadtop 20% of all pairs

Smell alikelow

Cooked together85 recipes

Shared aroma: ethyl acetate (pineapple, fruity).

Lemon and sugar barely smell alike, yet cooks put them together in 53,532 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

Confectioners' sugar: Provides sweetness and bulk, and thickens the liquid into a spreadable frosting as it dissolves.
Lemon juice: Adds acidity that brightens the sweetness of the sugar.