Name: Rock Cake
Ingredients: 1 cup sugar; 2 tablespoons butter; 2 eggs; 2 cups flour; 2 teaspoons Magic Baking Powder; 2 cups currants

Why it works: Butter and flour are a kitchen classic. They rank in the top 12% of all ingredient pairs, and cooks put them together in 124,287 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓

Rock Cake

Ingredients

Directions

The book gives no oven temperature. The 350°F (175°C) in the steps was added when the recipe was transcribed, as a starting point. The book gives no cooking times either; the times in the steps were added in transcription, so check for doneness rather than trusting the clock.

Prepare

Preheat your oven to 350°F (175°C).

Make the batter

In a bowl, cream together the sugar and butter.
Beat in the eggs one at a time.
Mix in the flour and Magic Baking Powder until combined.
Fold in the currants.

Bake

Drop spoonfuls of the mixture onto a baking sheet.
Bake for 15-20 minutes or until golden.

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 + flourtop 12% of all pairs

Smell alikelow

Cooked together124,287 recipes

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

Smell alikemoderate

Cooked together92,116 recipes

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

Smell alikelow

Cooked together106,462 recipes

Shared aroma: isobutyraldehyde (malty, green).
Butter + curranttop 17% of all pairs

Smell alikemoderate

Cooked together7,856 recipes

Shared aroma: isoamyl acetate (banana, pear).
Butter + eggtop 17% of all pairs

Smell alikemoderate

Cooked together118,967 recipes

Shared aroma: decanal (soap, orange peel).

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

Butter: Adds fat that makes the batter tender and rich while creaming with sugar.
Eggs: Bind the batter and add structure and moisture to the cakes.
Flour: Provides the structure that holds the cakes together as they bake.
Magic baking powder: Releases gas during baking so the cakes rise and stay light.
Currants: Add pockets of sweetness and chewy texture throughout the cakes.