Why it works: Milk and vanilla are a kitchen classic. They rank in the top 5% of all ingredient pairs, and cooks put them together in 19,187 recipes. Both carry ethyl caproate, which smells fruity, apple peel. The science ↓
Caramel Icing
Ingredients
Directions
Make the caramel base
Combine 2 cups brown sugar, 1 cup milk, and an egg-sized piece of butter in a saucepan.
Boil until it ropes.
Make the batter
Rub together 1 cup sugar and 1 tablespoon butter.
Break 2 or 3 eggs into a coffee cup and beat them, then fill the cup with milk.
Add a pinch of salt.
Mix in 1 ½ cups flour and 1 teaspoon baking powder.
Make the sugar syrup and finish
Place 1 cup sugar in a saucepan with enough water to meet it.
Boil without stirring.
Drop a small amount into cold water until it stiffens.
Stir constantly until it cools.
Add vanilla.
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.
Photo for illustrative purposes only · Contact us to use it
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.
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Milk + vanillatop 5% of all pairsSmell alikemoderateCooked together19,187 recipes
Shared aroma: ethyl caproate (fruity, apple peel).
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Milk + buttertop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
-
Sugar + vanillatop 8% of all pairsSmell alikelowCooked together35,032 recipes
Shared aroma: beta-damascenone (apple, rose).
-
Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
-
Flour + vanillatop 12% of all pairsSmell alikemoderateCooked together19,241 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
- Brown sugar
- Provides sweetness and caramel flavour as it boils down into the icing base.
- Eggs
- Add protein that helps the mixture set and gives it body.
- All-purpose flour
- Thickens the mixture and gives it structure as it sets.
- Baking powder
- Produces gas bubbles that lighten the texture.
- Butter
- Adds fat for richness and a smoother, softer texture.
The step that matters
Boil without stirring. Sugar syrup that is stirred while boiling can crystallise, turning grainy instead of smooth. Stirring is held back until the syrup has cooled, which keeps the icing creamy.
Swap the vanilla
How well each one fits the dish's main ingredients (sugar, milk, egg, butter, flour):
- Vanillathe original
- Raisinfits about as well
- Figfits less well
- Coconutfits less well
Fit is the average pairing score against sugar, milk, egg, butter, flour. 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.
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