Name: Sugar Cookies
Ingredients: 1 cup sugar; 1 egg; a little nutmeg; ⅔ cup shortening; ½ cup sour milk; ½ teaspoon baking soda; ½ teaspoon salt; flour (to make soft dough); granulated sugar (for sprinkling)

Why it works: Nutmeg and flour are a kitchen classic. They rank in the top 8% of all ingredient pairs, and cooks put them together in 18,623 recipes. Both carry isobutyraldehyde, which smells malty, green. The science ↓

Sugar Cookies

Oven, in the book's wordsA brisk oven

Ingredients

Directions

The book says “a brisk oven”. The 400°F (200°C) in the steps is the modern equivalent, not the book's own figure.

Prepare

Preheat the oven to 400°F (200°C).

Make and shape the dough

In a bowl, mix together sugar, egg, nutmeg, shortening, sour milk, baking soda, and salt.
Add enough flour to form a soft dough.
Roll the dough thin and sprinkle with granulated sugar.
Cut into desired shapes and bake until lightly 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.

Nutmeg + flourtop 8% of all pairs

Smell alikemoderate

Cooked together18,623 recipes

Shared aroma: isobutyraldehyde (malty, green).
Milk + flourtop 14% of all pairs

Smell alikelow

Cooked together78,219 recipes

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

Smell alikemoderate

Cooked together92,116 recipes

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

Smell alikemoderate

Cooked together14,685 recipes

Shared aroma: eucalyptol (eucalyptus, herbal).
Egg + flourtop 15% of all pairs

Smell alikelow

Cooked together106,462 recipes

Shared aroma: isobutyraldehyde (malty, green).

Milk and flour barely smell alike, yet cooks put them together in 78,219 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

Shortening: Adds fat that keeps the cookies tender and rich in texture.
Sour milk: Its acidity reacts with the baking soda so the cookies rise and soften.
Baking soda: Reacts with the acidic sour milk to produce gas that lifts the dough.
Egg: Binds the dough and adds structure and richness.
Sugar: Sweetens the cookies and helps them brown during baking.