Name: Brownies
Ingredients: 2 squares Baker's chocolate; 1 cup sugar; ½ cup chopped walnuts; ½ cup flour; ½ cup butter; 2 eggs; 1 teaspoon vanilla

Why it works: Chocolate and vanilla are a kitchen classic. They rank in the top 5% of all ingredient pairs, and cooks put them together in 10,020 recipes. Both carry sotolon, which smells curry, maple. The science ↓

Brownies

Oven, in the book's wordsA hot oven

Ingredients

Directions

The book says “a hot oven”. The 300°F (150°C) in the steps is the modern equivalent, not the book's own figure.

Make the batter

Melt the chocolate and butter together.
In a bowl, mix the melted chocolate and butter with sugar, eggs, and vanilla.
Stir in the flour and walnuts until combined.

Bake and serve

Pour the batter into a greased baking sheet.
Bake at 300°F (150°C) for 40 minutes.
Cut into squares after cooling.

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.

Chocolate + vanillatop 5% of all pairs

Smell alikemoderate

Cooked together10,020 recipes

Shared aroma: sotolon (curry, maple).
Sugar + vanillatop 8% of all pairs

Smell alikelow

Cooked together35,032 recipes

Shared aroma: beta-damascenone (apple, rose).
Walnut + vanillatop 10% of all pairs

Smell alikestrong

Cooked together2,730 recipes

Shared aroma: eucalyptol (eucalyptus, herbal).
Chocolate + walnuttop 10% of all pairs

Smell alikemoderate

Cooked together1,548 recipes

Shared aroma: 3-ethyl-2,5-dimethylpyrazine (roasted, nutty).
Flour + buttertop 12% of all pairs

Smell alikelow

Cooked together124,287 recipes

Shared aroma: isobutyraldehyde (malty, green).

Sugar and vanilla barely smell alike, yet cooks put them together in 35,032 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

Eggs: Bind the batter and add structure and richness as they set in the oven.
Flour: Provides structure so the batter sets into a cut-able square rather than a pudding.
Butter: Adds fat for a tender, moist texture and carries the chocolate flavour.
Sugar: Adds sweetness and helps give the brownies a moist, tender crumb.
Baker's chocolate: Supplies the chocolate flavour and fat that define the brownie's richness.

The step that matters

Bake at 300°F (150°C) for 40 minutes. Baking too long dries out the brownies and sets the centre too firmly. Pull them when the surface looks set and a tester comes out with a few moist crumbs, since carryover heat continues cooking the batter as it cools.

Swap the walnut

How well each one fits the dish's main ingredients (chocolate, sugar, flour, butter, egg, vanilla):

Almondfits better
Hazelnutfits better
Macadamia nutfits better
Walnutthe original

Fit is the average pairing score against chocolate, sugar, flour, butter, egg, vanilla. Candidates are from the same food group and used in at least 100 recipes.

“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.