Name: Hard Sauce
Ingredients: 2 cups powdered sugar; ½ cup sweet butter; Boiling water (as needed); Vanilla extract (optional); Nutmeg (optional, for apple puddings); Lemon juice or wine (optional, for rice puddings)

Why it works: Nutmeg and lemon match in chemistry and in kitchens. They rank in the top 5% of all ingredient pairs, and cooks put them together in 11,318 recipes. Both carry beta-phellandrene, which smells minty, terpene. The science ↓

Hard Sauce

Ingredients

2 cups powdered sugar
½ cup sweet butter
Boiling water (as needed)
Vanilla extract (optional)
Nutmeg (optional, for apple puddings)
Lemon juice or wine (optional, for rice puddings)

Directions

Make the sauce

In a bowl, stir together the powdered sugar and sweet butter until well combined.
If desired, add flavoring to taste.
To thin for cream or plain batter pudding, mix in a few tablespoons of boiling water.

Flavor for the pudding

For apple puddings, add nutmeg for flavor.
For rice puddings, incorporate a little lemon juice or wine.

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 + lemontop 5% of all pairs

Smell alikestrong

Cooked together11,318 recipes

Shared aroma: beta-phellandrene (minty, terpene).
Vanilla + appletop 8% of all pairs

Smell alikemoderate

Cooked together1,501 recipes

Shared aroma: beta-damascenone (apple, rose).
Sugar + vanillatop 8% of all pairs

Smell alikelow

Cooked together35,032 recipes

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

Smell alikestrong

Cooked together2,781 recipes

Shared aroma: eucalyptol (eucalyptus, herbal).
Nutmeg + appletop 12% of all pairs

Smell alikemoderate

Cooked together3,790 recipes

Shared aroma: estragole (anise, licorice).

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

Powdered sugar: Sweetens the sauce and dissolves smoothly into the butter for a soft, spreadable body.
Sweet butter: Provides fat and richness, giving the sauce a creamy mouthfeel once it is combined with the sugar.
Boiling water: Thins the sauce to a pourable consistency so it can be spread over or mixed into puddings.

Swap the vanilla

The recipe marks vanilla as optional. How well each one fits the dish's main ingredients (sugar, butter, nutmeg, apple, lemon):

Figfits about as well
Orangefits about as well
Blackberryfits about as well
Vanillathe original

Fit is the average pairing score against sugar, butter, nutmeg, apple, lemon. 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.