Why it works: Butter and milk are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 81,283 recipes. Both carry (z)-4-heptenal, which smells biscuit, cream. The science ↓
Boston Cream Cakes
Ingredients
Directions
The book says “a hot oven”. The 400°F (200°C) in the steps is the modern equivalent, not the book's own figure.
Make the choux paste
Boil the water in a clean kettle over a coal fire.
Add the butter to the boiling water, then stir in the flour until free from lumps.
Pour the mixture out to cool, then beat in the eggs one at a time.
Butter some baking sheets and drop the mixture in small rounds.
Bake and make the custard
Bake in a hot oven at 400°F (200°C) for 15 to 20 minutes.
For the custard, mix ¼ pound of flour with a little milk.
Boil 1 quart of milk, then stir in the flour mixture and boil hard for 1 minute.
Beat 4 eggs and stir them into the hot mixture, then add ½ pound of sugar, salt, and lemon essence.
Fill and serve
When the biscuits are cold, make an incision in one side and fill with custard.
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.
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 + milktop 7% of all pairsSmell alikemoderateCooked together81,283 recipes
Shared aroma: (z)-4-heptenal (biscuit, cream).
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Butter + flourtop 12% of all pairsSmell alikelowCooked together124,287 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Flour + milktop 14% of all pairsSmell alikelowCooked together78,219 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Flour + sugartop 15% of all pairsSmell alikemoderateCooked together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
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Milk + lemontop 15% of all pairsSmell alikemoderateCooked together19,053 recipes
Shared aroma: 2-nonenal (fatty, green).
Butter and flour barely smell alike, yet cooks put them together in 124,287 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
- Bind the paste and set the custard, giving structure and richness.
- Flour
- Thickens the paste and custard, giving body and structure.
- Butter
- Adds fat to the boiling water for richness and tenderness in the paste.
- Milk
- Forms the liquid base of the custard, giving it creaminess.
- Sugar
- Sweetens the custard and balances its richness.
The step that matters
Boil the custard flour mixture hard for 1 minute. Flour starch only thickens fully when it reaches a boil, and boiling hard for a full minute cooks out raw starch taste. Stopping early leaves a thin, floury custard.
Swap the lemon
How well each one fits the dish's main ingredients (butter, flour, egg, milk, sugar):
- Vanillafits better
- Raisinfits better
- Figfits better
- Lemonthe original
Fit is the average pairing score against butter, flour, egg, milk, 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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