Why it works: Vanilla and milk 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 ↓
Soft Custard
Ingredients
Directions
Prepare
Heat the milk in a saucepan.
In a bowl, mix the egg yolks, sugar, and salt.
Make the custard
Slowly add the hot milk to the bowl while stirring.
Cook the mixture over hot water, stirring constantly, until it thickens enough to coat the back of a spoon.
Strain the custard, let it cool, and then add the vanilla extract.
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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Vanilla + milktop 5% of all pairsSmell alikemoderateCooked together19,187 recipes
Shared aroma: ethyl caproate (fruity, apple peel).
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Sugar + vanillatop 8% of all pairsSmell alikelowCooked together35,032 recipes
Shared aroma: beta-damascenone (apple, rose).
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Egg + milktop 18% of all pairsSmell alikemoderateCooked together88,785 recipes
Shared aroma: 2-nonenal (fatty, green).
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Sugar + milktop 18% of all pairsSmell alikelowCooked together77,875 recipes
Shared aroma: 2-nonenal (fatty, green).
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Egg + sugartop 21% of all pairsSmell alikemoderateCooked together122,807 recipes
Shared aroma: 2-nonenal (fatty, 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
- Egg yolks
- Thicken the custard as they set when gently heated, giving it body and richness.
- Milk
- Forms the liquid base that the egg yolks thicken into a smooth custard.
- Sugar
- Adds sweetness and balances the richness of the yolks and milk.
The step that matters
Cook the mixture over hot water, stirring constantly. Egg yolks thicken as their proteins set with gentle heat. If the heat is too high or stirring stops, the yolks can scramble and curdle, so the custard must be cooked slowly and stirred until it coats a spoon.
“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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