Why it works: Sugar and lemon are a kitchen classic. They rank in the top 18% of all ingredient pairs, and cooks put them together in 53,532 recipes. Both carry 2-nonenal, which smells fatty, green. The science ↓
Plain Frosting
Ingredients
Directions
Make the frosting
Place the egg white in a bowl.
Add 1 tablespoon of powdered sugar and beat with a wooden spoon.
Gradually add more sugar by the spoonful, beating well after each addition.
Continue until the frosting leaves a clean-cut line when drawn with a knife.
Frost the cake
Frost the cake while it is warm, starting with a thin coating to fill the pores.
Spread a thicker layer evenly over the entire surface.
Mark where to cut and set in a cool place to harden.
If the frosting is too stiff, thin it with lemon juice.
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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Sugar + lemontop 18% of all pairsSmell alikelowCooked together53,532 recipes
Shared aroma: 2-nonenal (fatty, green).
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Egg + lemontop 19% of all pairsSmell alikelowCooked together44,316 recipes
Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
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Egg + sugartop 21% of all pairsSmell alikemoderateCooked together122,807 recipes
Shared aroma: 2-nonenal (fatty, green).
Sugar and lemon barely smell alike, yet cooks put them together in 53,532 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
- Egg white
- Whipped with sugar, it forms the foam that gives the frosting its light, spreadable structure.
- Powdered sugar
- Dissolves into the egg white to add sweetness and body, thickening the frosting as it sets.
The step that matters
Adding the sugar gradually. Sugar added a spoonful at a time dissolves fully into the egg white and keeps the foam stable. Adding it all at once can leave lumps and leave the frosting too stiff or too loose to spread evenly.
Swap the lemon
The recipe marks lemon as optional. How well each one fits the dish's main ingredients (egg, sugar):
- Vanillafits better
- Raisinfits about as well
- Lemonthe original
- Datesfits less well
Fit is the average pairing score against egg, sugar. 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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