Sponge and panna cotta birthday cake

Virtually all of my family’s birthdays fall in April and May; this week it’s the CCM’s turn. I wanted to make her something that was clearly a cake but, at the same time, I know she has a passion for panna cotta.

This cake is my own invention – it’s effectively a hollowed out sponge filled with creamy panna cotta and then topped off with beautiful fruit, including luscious English strawberries.

My main concern was that as the panna cotta is liquid until set it would leak through the sponge. By lining the inside of the tin with plenty of clingfilm it meant that none of the liquid could escape – and it was rather tasty how it set in the sponge making it succulent; the best way to describe it is like an even creamier tres leche cake.

I will admit that for an hour after I put the panna cotta filled sponge into the fridge I couldn’t walk by without gingerly opening the fridge door and peering in to make sure none had escaped. It’s amazing how much tension you can build into making a cake!

Any spare panna cotta that won’t fit in the sponge can simply be poured into ramekins and enjoyed as a bonus dessert. The quantities I provide below filled my cake and four ramekins.

You can fit more panna cotta in the cake if you make a double tier of sponge around the side of the cake (I realise I sound a total gutbucket saying that but, let’s be honest, the only thing better than panna cotta is more panna cotta!). As sponge is soft and bendy you can keep cutting the sponge in concentric circles and then pressing these into the sides – they will shape to the curve of the tin. This is one of those things that’s quite wordy to describe but a picture will make it clearer.

Here’s the single tier sponge bowl:

You can see how much extra height you get by adding a second tier. Here it is in progress:

My lovely sponge bowl (not to be confused with the Superbowl, which is far less interesting):

The only sponge I had left at the end was the top I cut off to level the cake and a tiny disc.

Happy birthday CCM!

Ingredients

For the cake:
250g unsalted butter, at room temperature
220g caster sugar
1 teaspoon vanilla extract
4 eggs
80ml milk
300g self raising flour

For the panna cotta:
12 gelatine leaves
1l milk (anything but skimmed – does that even contain milk?)
1l double cream
4 vanilla pod, cut open and seeds scraped out
100g caster sugar

To decorate: whipped cream and fresh fruit

Method

Preheat the oven to 180°C/fan oven 160°C/350°F/Gas mark 4.

Line the base of a 20cm springform deep baking tin with baking paper.

Start by making the sponge: Beat together the butter, sugar and vanilla until light and fluffy. Don’t skimp on this stage as this is when you get lots of lovely air into your sponge.

Beat in the eggs gradually, add some of the flour if it looks like it might curdle.

Beat in the milk.

Stir in the flour until the mixture is smooth and well combined.

Spoon into the prepared tins and level the surface.

Bake for approximately 30 minutes or until a skewer inserted into the centre of the sponge comes out clean. Another good sign is if the sponge is just pulling away from the edge of the tin.

Leave to cool in the tin for about 20 minutes before turning out and leaving to cool completely on a wire rack.

You can make the sponge the day before the panna cotta. In fact, this is a good idea as it gives time for the sponge to firm up.

Cut a slice, about 2cm thick off the base of the sponge - this will be the bottom to your finished cake.

Line the springform tin you baked the cake in with clingfilm, then wrap the outside in foil. This is so no panna cotta can escape while it’s setting.

Sit the disc of sponge in the bottom of the lined tin.

Level the sponge by slicing the top off. This off cut will not be used in the cake so either eat, or use for a trifle base etc.

You will now have the middle disc of sponge. Cut a circle out of this, careful not to damage the sides. The size of the circle you cut out will determine how much panna cotta you can fill the sponge with – I aimed to leave an edge of approx 1.5cm thickness.

Sit the “O” shaped outer piece in the lined tin above the base sponge. You now have your ‘sponge bowl’ to fill with panna cotta. You can build a second tier by cutting another ring out of the remaining sponge – it is soft enough to mould to the curve of the tin.

Now make the panna cotta: Soak the gelatine leaves in a bowl of cold water until they are soft.

Place the milk, cream, vanilla pod, vanilla seeds and sugar in a saucepan and bring to a simmer.

Discard the vanilla pod.

Squeeze as much water as you can out of the gelatine leaves and whisk into the creamy mixture. It will dissolve pretty quickly but make sure you’ve thoroughly whisked it in as you don’t want lumps.

Ladle the mixture into your sponge bowl and press a sheet of clingfilm onto the surface of each – this stops a skin forming. If the sponge comes up above the height of the tin (mine did, as I had a double tier of sponge) ensure that you only fill up the top of the tin – not the sponge.

If you have any panna cotta left over, spoon it into ramekins and eat these as dessert! I had enough left over for four full ramekins.

Leave to cool before refrigerating for at least a couple of hours (overnight is best).

When ready to serve decorate with whipped cream and fruit.

Bask in the glory of the wonderful thing you have made.

Eat.