Why it works: Sugar and flour are a kitchen classic. They rank in the top 15% of all ingredient pairs, and cooks put them together in 92,116 recipes. Both carry phenylacetaldehyde, which smells hawthorne, honey. The science ↓
Hot Water Sponge Cake
Ingredients
Directions
The book gives no oven temperature. The 350°F (175°C) in the steps was added when the recipe was transcribed, as a starting point. The book gives no cooking times either; the times in the steps were added in transcription, so check for doneness rather than trusting the clock.
Prepare
Preheat your oven to 350°F (175°C).
Make the batter
In a mixing bowl, beat the eggs until light and fluffy.
Gradually add the sugar and salt, continuing to beat until well combined.
Sift together the flour and baking powder, then fold into the egg mixture.
Stir in the boiling water and lemon extract until smooth.
Bake
Pour the batter into a greased cake pan and bake for 25-30 minutes or until a toothpick comes out clean.
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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Sugar + flourtop 15% of all pairsSmell alikemoderateCooked together92,116 recipes
Shared aroma: phenylacetaldehyde (hawthorne, honey).
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Egg + flourtop 15% of all pairsSmell alikelowCooked together106,462 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Flour + lemontop 17% of all pairsSmell alikemoderateCooked together30,404 recipes
Shared aroma: isobutyraldehyde (malty, green).
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Sugar + lemontop 18% of all pairsSmell alikelowCooked together53,532 recipes
Shared aroma: 2-nonenal (fatty, green).
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Egg + lemontop 19% of all pairsSmell alikelowCooked together44,316 recipes
Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
Egg and flour barely smell alike, yet cooks put them together in 106,462 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
- Whipped into foam that traps air, giving the cake its light, airy structure.
- Flour
- Sets during baking as its starch gelatinizes, forming the cake's crumb structure.
- Sugar
- Adds sweetness and helps stabilize the whipped eggs while browning the crust.
- Baking powder
- Releases gas in the batter, helping the cake rise and become tender.
- Boiling water
- Melts the sugar and adds moisture, keeping the cake soft and spreading the batter.
The step that matters
Folding in the flour. Flour is added to whipped eggs, and overmixing or deflating the foam knocks out the air bubbles that give the cake its lift. Fold gently, only until no dry flour streaks remain.
Swap the lemon
How well each one fits the dish's main ingredients (egg, sugar, flour):
- Raisinfits better
- Vanillafits better
- Lemonthe original
- Figfits about as well
Fit is the average pairing score against egg, sugar, flour. 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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