Take a trip back in time with this retro school cake! Vanilla sponge is topped with icing and sprinkles to make this traybake that will bring back childhood memories and the highlight of the week in primary school lunch terms. This easy one bowl recipe is a fun and easy bake to make with your kids too.
School sponge cake was such a popular cake at school. It made school lunches bareable! A soft vanilla sponge topped with icing and lots of sprinkles makes this school cake recipe one that is loved by older and younger family members alike, whether you have memories of it or not. Following on with my nostalgic journey through memory lane after publishing this almond slice recipe, chocolate tiffin and choc coconut slice I thought I’d turn my attention to this old school sponge.
Why we love this recipe
- This simple sponge cake recipe is guaranteed to bring a smile to your face; whether you remember eating it at primary school (like me), or love cake with icing and colourful sprinkles (like mini Jones).
- It’s an easy one bowl recipe that uses store cupboard ingredients.
- Using equal weights for eggs, flour, sugar and margarine / butter mean it’s very hard to get wrong. It’s based off the weight of eggs in their shells, meaning whether you use size large eggs or medium eggs, you are pretty guaranteed to get a delicious soft sponge tray bake.
- This old fashioned school cake is great for birthday parties, bake sales and picnics, and when you just want to bake some cake!
- The cake is light and fluffy, but sturdy enough to easily transport, and despite it’s simplicity, so delicious it always brings a smile to your face!
Ingredients Notes and Substitutions
- Flour – plain flour or all purpose flour.
- Margarine – as this is a retro cake recipe I have used margarine, as I am pretty confident that is what would be used back in my school days! You can use unsalted butter if you prefer, however it will alter the taste and texture ever so slightly. Unsalted butter will still make a delicious vanilla sponge tray bake, but if you are after that old school taste you won’t get it with butter.
- Sugar – white sugar or granulated sugar.
- Eggs – size large.
- Vanilla extract – or vanilla essence if you want to stick with the school theme. Provides that lovely vanilla sponge taste.
- Icing sugar – confectioners sugar. I prefer to use pure icing sugar rather than soft icing sugar, but either will work.
- Sprinkles – aka hundreds and thousands, sugar strands.
How to make this sprinkle cake
- Weigh the eggs (in their shells) and use this weight for your flour and sugar and margarine. As you can see from picture 1. the combined weight of my 4 eggs is 242 grams.
- In a medium mixing bowl combine the margarine, sugar and vanilla and beat with a spoon or use an electric whisk/beaters until soft, fluffy and light.
- Add one egg and stir.
- Mix the flour with the baking powder then add a quarter of this mixture and stir. Repeat with the rest of the eggs and the rest of the flour.
- Add the milk and stir.
- Spoon the sponge batter in to a prepared tin lined with baking paper / baking parchment. Bake until golden and a skewer inserted in to the middle of the sponge comes out clean.
- Once the sponge cake has cooled, make the water icing. Sift the icing sugar into a bowl then add the water a drop at a time until you get a thick icing.
- Spoon the icing over the cake.
- Quickly scatter the sprinkles / 100s and 1000s over the icing whilst still wet.
Freeze the sponge cake un-iced, for up to 3 months. Cool the cake completely then wrap well. To thaw leave the cake in the fridge overnight, or at room temperature for 2-3 hours before serving. Drizzle over the icing and sprinkles once thawed.
The icing prevents the air from getting to the top of the sponge cake, which is the thing that make cake become hard and dry, but to prevent any hairs or specks of dust from getting to the icing it’s best to cover the cake with an upturned bowl or container overnight.
My Recipe Tips
- Don’t overmix the batter. Stop mixing when the flour and egg have just been combined in to the mixture, and then the same with the milk.
- The icing should be thick. If it’s too runny it will run off the sides of the cake. If you add too much water and the icing is too runny, sift in a little more icing sugar / confectioners sugar.
- Have the sprinkles ready to sprinkle over the icing as it will soon dry enough and the sprinkles can fall off, and your old school tray bake will not look as colourful!
- Smaller square cake: You can make this tray bake cake in an 20 cm x 20 cm (8″ x 8″) square tin. Use three eggs, weigh them and use this amount for the flour, sugar and margarine. Bake for 25-30 minutes.
- This cake will keep in an airtight container at room temperature for up to 3-4 days, after this time it begins to dry out.
- If you want to freeze the cake, freeze it un-iced.
More bakes you may like
If you are a fan of tray bakes, these easy slices are all guaranteed to put a smile on your face.
- 4 eggs, weighed in the shell. Mine weighed 242g ($1.40 / £0.72p)
- 242 g margarine or butter, softened ($1.35 / £0.58p)
- 242 g white sugar ($0.27 / £0.15p)
- 2 teaspoons vanilla essence, or vanilla bean paste ($0.08/ £0.04p)
- 242 g plain flour ($0.30 / £0.13p)
- 2 teaspoons baking powder ($0.20 / £0.06p)
- 1-2 tablespoons milk ($0.13 / £0.02p)
- 200g (2½ c) icing sugar / confectioners sugar ($0.72 / £0.36p)
- cold water ($0 / £0)
- sprinkles / 100s and 1000s ($0.28 / £0.30p)
- Preheat the oven to 160˚C fan / 180˚C / 320˚F convection / 356˚F
- Line a 20cm x 27cm (8" x 6") tin with baking paper / baking parchement
- Weigh the four eggs in their shells and use this amount for the margarine/butter, white sugar and plain flour.
- Cream the margarine and sugar with vanilla until pale and fluffy (you can do this by hand with a spoon or in a food processor).
- Mix the flour with baking powder.
- Add one egg to the margarine / sugar and stir lightly before adding ¼ of the flour.
- Repeat with the remaining eggs and flour.
- Add 1 tablespoon milk and mix, adding a little more if the mixture looks dry – it should just drop off the spoon.
- Spoon in to the prepared tin and bake for 30-35 minutes until a skewer inserted into the middle of the cake comes out clean.
- Cool in the tin for 10 minutes before turning out to a wire rack to cool completely.
- When completely cold, prepare the icing: sift the icing sugar / confectioners sugar in to a bowl and add a little water at a time, until you get a smooth thick icing.
- Spoon the icing over the cake then sprinkle with sprinkles straight away whilst the icing is wet.
- Cut in to pieces and enjoy!
- Store in an airtight container for 3-4 days.