Name: Butter Cups
Ingredients: 4 pounds stiff vanilla fondant; lozenge sugar for dusting; 5 pounds sugar; ½ teaspoon cream of tartar; 1 quart water; ⅓ cup N. O. molasses; 6 to 8 ounces butter

Why it works: Cream and butter are a kitchen classic. They rank in the top 8% of all ingredient pairs, and cooks put them together in 41,516 recipes. Both carry delta-dodecalactone, which smells sweet, creamy. The science ↓

Butter Cups

Ingredients

Directions

Prepare the fondant

Place the fondant before a table heater on a sheet of tin.
Knead the fondant until hot.
Dust the tin with lozenge sugar to prevent sticking.

Make the candy

In a pot, combine sugar, cream of tartar, water, and molasses; cook until hard crack stage.
Add butter to the mixture and stir until combined.
Pour the mixture onto a slab and let it cool until manageable.
Spread the mixture into an even sheet large enough to cover the fondant.
Roll the fondant lengthwise and place it on the sheet.
Fold the sheet around the fondant, sealing the ends and sides tightly.
Warm the batch before the heater until it is workable.
Spin the mixture to the thickness of stick candy and the length of the table.
Cut off pieces with shears.
Have an assistant mark each stick with a caramel cutter while warm.
When cold, break them up.

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.

Cream + buttertop 8% of all pairs

Smell alikemoderate

Cooked together41,516 recipes

Shared aroma: delta-dodecalactone (sweet, creamy).
Vanilla + sugartop 8% of all pairs

Smell alikelow

Cooked together35,032 recipes

Shared aroma: beta-damascenone (apple, rose).
Sugar + creamtop 9% of all pairs

Smell alikemoderate

Cooked together43,450 recipes

Shared aroma: 2,3-butanedione (butter, sweet).
Sugar + molassestop 11% of all pairs

Smell alikemoderate

Cooked together9,225 recipes

Shared aroma: ethanol (alcoholic, ethereal).
Vanilla + buttertop 14% of all pairs

Smell alikemoderate

Cooked together20,050 recipes

Shared aroma: guaiacol (smoky, sweet).

Vanilla and sugar 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

Sugar: Forms the crystalline candy base that sets hard as it cooks to hard crack stage.
Butter: Adds fat and richness, softening the bite and rounding the flavor of the candy.
N. o. molasses: Adds depth, colour and a caramel-like flavour to the hard candy.
Cream of tartar: Acts as an acid that helps prevent sugar from crystallizing during cooking.

The step that matters

Cook to hard crack stage. Sugar syrup must reach the hard crack stage, around 300°F, so the candy sets hard and brittle when cool. Stopping early leaves a sticky, chewy result, while overcooking can scorch the molasses and sugar and taste bitter.

“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.