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 pot.
Add the butter to the boiling water and stir in the flour until smooth.
Pour the mixture out to cool completely.
Once cool, beat in the eggs one at a time until well combined.
Butter a baking sheet and drop small rounds of the mixture onto it.
Bake in a hot oven at 400°F (200°C) for 15 to 20 minutes.
Make the custard
In a separate pot, mix ¼ pound of flour with a little milk.
Boil the remaining milk and stir in the flour mixture, boiling for about 1 minute.
Beat the eggs and stir them into the hot mixture.
Add the sugar, salt, and lemon essence or oil.
Assemble
Once the biscuits are cool, 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
- Flour
- Starch in the paste and custard that gives the dough body and thickens the custard.
- Eggs
- Add structure and richness, and set the custard when heated.
- Butter
- Adds fat and richness to the paste, giving a tender interior.
- Milk
- Liquid for the custard that gives it creaminess and body.
- Sugar
- Adds sweetness and helps the custard taste rounded.
The step that matters
Drying and baking the rounds. The paste must be cooled before the eggs are added, or they will scramble. The rounds must bake fully until dry and crisp, or they will collapse or stay soggy and fail to hold the 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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