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 ↓
Soft Custard
Ingredients
Directions
Prepare the custard
Heat the milk in a saucepan.
In a bowl, mix the egg yolks, sugar, and salt.
Slowly add the hot milk to the mixture.
Cook the mixture over hot water, stirring constantly, until it thickens enough to coat the back of a spoon.
Finish and cool
Strain the custard.
Cool it.
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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Milk + vanillatop 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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Milk + eggtop 18% of all pairsSmell alikemoderateCooked together88,785 recipes
Shared aroma: 2-nonenal (fatty, green).
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Milk + sugartop 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 gently with heat, giving it body.
- Milk
- Forms the liquid base that the egg yolks thicken into a custard.
- Sugar
- Adds sweetness and softens the set of the custard.
The step that matters
Cooking over hot water while stirring constantly. Egg yolks thicken as proteins set with heat, but if they get too hot they can curdle or scramble. Gentle heat and constant stirring keep the custard smooth until it coats the back of 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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