Why it works: Butter and lemon 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 ↓
French Melted Butter
Ingredients
Directions
In a bowl, whisk the yolks of 2 or 3 eggs.
Gradually pour in ½ pint of boiling melted butter while stirring briskly.
Return the mixture to a saucepan and shake it over the heat for a moment, ensuring it does not boil.
Add a tablespoon of lemon juice or vinegar and serve immediately.
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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Butter + lemontop 16% of all pairsSmell alikemoderateCooked together41,227 recipes
Shared aroma: 3-hexenal (apple, fruity).
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Butter + eggtop 17% of all pairsSmell alikemoderateCooked together118,967 recipes
Shared aroma: decanal (soap, orange peel).
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Egg + lemontop 19% of all pairsSmell alikelowCooked together44,316 recipes
Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
Egg and lemon barely smell alike, yet cooks put them together in 44,316 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 yolks
- Emulsify the butter and thicken the sauce as they gently cook.
- Melted butter
- Provides the fat that gives the sauce its rich body and mouthfeel.
- Lemon juice or vinegar
- Adds acidity that brightens the buttery flavour and balances richness.
The step that matters
Keep the heat gentle when returning to the saucepan. Egg yolks begin to scramble above roughly 70°C, so the sauce can curdle if it boils. Brief, gentle shaking over the heat warms the yolks just enough to thicken them while keeping the emulsion smooth.
Swap the lemon
How well each one fits the dish's main ingredients (butter, egg):
- Lemonthe original
- Vanillafits about as well
- Coconutfits about as well
- Raspberryfits less well
Fit is the average pairing score against butter, egg. 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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