Name: Black and White Cookie Bars
Prep time: 20 min
Cook time: 25 min
Yield: 24
Ingredients: 2 whole Eggs; ¾ cups Butter, At Room Temperature; ½ cups Brown Sugar, Firmly Packed; ¾ cups White Granulated Sugar; ½ cups Dark Chocolate Cocoa Powder; ½ teaspoons Salt; ½ teaspoons Baking Soda; 2 cups Flour; 1-½ cup White Chocolate Chips; 1 cup Semi-Sweet Chocolate Chips

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 ↓

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 + chocolatetop 13% of all pairs

Smell alikemoderate

Cooked together15,404 recipes

Shared aroma: guaiacol (smoky, sweet).
Cocoa powder + flourtop 13% of all pairs

Smell alikemoderate

Cooked together2,244 recipes

Shared aroma: phenylacetaldehyde (hawthorne, honey).
Sugar + cocoa powdertop 14% of all pairs

Smell alikemoderate

Cooked together2,920 recipes

Shared aroma: guaiacol (smoky, sweet).
Butter + cocoa powdertop 14% of all pairs

Smell alikemoderate

Cooked together2,130 recipes

Shared aroma: 2,3-pentanedione (butter, sweet).

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

Ingredient	Portion assumed	kcal
Flour	1 cup (125g) all-purpose	455
Chocolate	1 oz (28g) semisweet	155
Butter	1 tbsp (14g)	102
Egg	1 large egg (50g)	78
Sugar	1 tbsp (12.5g) granulated	49
Salt	1 tsp (6g)	0

Black and White Cookie Bars