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 ↓
Rock Cakes
Ingredients
Directions
The book says “a brisk oven”. The 400°F (200°C) in the steps is the modern equivalent, not the book's own figure.
Prepare the dough
In a bowl, cream the butter with the baking powder until smooth.
Gradually work in the flour.
Add the currants (picked and dried), sugar, mixed peel (finely cut), and grated lemon rind.
Beat the egg and mix it with the milk.
Stir this into the mixture until stiff.
Shape and bake
Place small knobs of the mixture, about the size of a walnut, on a floured baking sheet, spaced 1.5 inches apart.
Bake in a brisk oven at 400°F (200°C) until golden.
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 + 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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Lemon + milktop 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
- Butter
- Creamed with the baking powder, it gives the cakes a tender, short crumb and richness.
- Flour
- Forms the structure that holds the knobs together and sets as the cakes bake.
- Baking powder
- Releases gas during baking, helping the cakes rise and stay light.
- Currants
- Add sweetness and chewy fruit pieces that stay distinct in the baked cake.
- Egg
- Binds the mixture and adds structure and richness to the cakes.
- Milk
- Adds moisture so the stiff mixture comes together and stays soft inside.
The step that matters
Stiffening the mixture before shaping. Stirring in the egg and milk must stop once the dough is stiff. Overmixing develops gluten in the flour, making the rock cakes tough and dense rather than tender.
Swap the currant
How well each one fits the dish's main ingredients (butter, lemon, flour, egg, milk, sugar):
- Vanillafits better
- Raisinfits better
- Figfits better
- Currantthe original
Fit is the average pairing score against butter, lemon, 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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