Why it works: Lemon and butter are a kitchen classic. They rank in the top 16% of all ingredient pairs, and cooks put them together in 41,227 recipes. Both carry 3-hexenal, which smells apple, fruity. The science ↓
Lemon Custard
Ingredients
Directions
The book gives no oven temperature. The 350°F (175°C) in the steps was added when the recipe was transcribed, as a starting point. The book gives no cooking times either; the times in the steps were added in transcription, so check for doneness rather than trusting the clock.
Prepare
Preheat the oven to 350°F (175°C).
Make the custard
Beat the egg yolks with the sugar until smooth.
Beat the egg whites until stiff peaks form, then gently fold them into the yolk mixture.
Grate the lemon peel and squeeze in the juice from the lemons.
Add the small piece of butter and mix well.
Bake
Pour the mixture into a baking dish and bake until set, about 30-40 minutes.
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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Lemon + buttertop 16% of all pairsSmell alikemoderateCooked together41,227 recipes
Shared aroma: 3-hexenal (apple, fruity).
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Egg + buttertop 17% of all pairsSmell alikemoderateCooked together118,967 recipes
Shared aroma: decanal (soap, orange peel).
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Sugar + buttertop 17% of all pairsSmell alikemoderateCooked together98,233 recipes
Shared aroma: guaiacol (smoky, sweet).
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Sugar + lemontop 18% of all pairsSmell alikelowCooked together53,532 recipes
Shared aroma: 2-nonenal (fatty, green).
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Lemon + eggtop 19% of all pairsSmell alikelowCooked together44,316 recipes
Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
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
- Eggs
- Egg yolks set the custard and whites, folded in, lighten its texture.
- Sugar
- Sweetens the custard and helps the yolks blend smoothly.
- Lemons
- Juice and peel add acidity and bright lemon aroma.
- Butter
- Adds richness and a silky mouthfeel to the custard.
The step that matters
Folding the egg whites. Folding gently keeps the whipped whites airy; stirring hard deflates them, leaving a denser, less light custard.
Swap the lemon
How well each one fits the dish's main ingredients (sugar, egg, butter):
- Vanillafits better
- Lemonthe original
- Raisinfits about as well
- Figfits about as well
Fit is the average pairing score against sugar, egg, butter. 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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