Custard Cream Cake

Can't decide between a slice of cake or a biscuit?  Try this!!

As a kid my favourite biscuits were always Custard Creams so when I saw the recipe for Custard Cream Cupcakes in the new Hummingbird Bakery cookbook 'Home Sweet Home' I was inspired to make this cake.  Most recipes use custard powder which I find gives a weird chalky flavour and texture that I really don't like.  This one however uses a creme pattissiere flavoured with vanilla pods so you don't get any of that nasty cornfloury-ness (yes it's a word!?!)
I have changed the recipe quite a bit but the original can be found in 'Home Sweet Home'. There are lots of stages but none of them take too long, the biscuits and creme pattissiere can be made a day in advance.

For the Biscuits:
100g soft unsalted butter
100g caster sugar
1 large egg
1/2 tsp vanilla bean paste
200g plain flour
1/4 tsp cream of tartar

Beat the butter and sugar til combined then mix in the egg and vanilla paste.
Stir in the flour and cream of tartar to form a soft dough.  Wrap in clingfilm and chill for around 20 minutes.
Preheat the oven to 170 degrees C / 325 degrees F / Gas mark 3.
Line 2 baking sheets with greaseproof paper.
Roll out the dough fairly thinly (3-4mm).  I always roll the dough out between 2 sheets of greaseproof paper or clingfilm to avoid it sticking without adding any extra flour as this can make the biscuits tough.  Cut out as many biscuits as you can, I used a 5cm round cutter but you can use whatever shape you prefer.  Keep re-rolling and cutting until all the dough is used up.
Transfer the biscuits to the lined trays and bake for 8-10 minutes til lightly golden at the edges.  If you have cut much larger biscuits they may take a little longer.  Cool completely on a wire rack.

For the Vanilla Creme Patissiere:
120ml milk
100ml single cream
1 vanilla pod, split lengthways
2 egg yolks
40g caster sugar
15g cornflour
15g plain flour

Heat the milk, cream and vanilla pod til boiling, do this slowly and stir regularly to avoid scorching.
Mix the egg yolks, sugar, cornflour and flour to a smooth paste in a large bowl.  Add 1-2 tbsp of the hot milk if needed.
Remove the vanilla pod then pour the boiling milk mixture over the paste, whisking all the time then quickly pour back into the pan.
Keep whisking over a low heat until the mixture thickens, this should take 4-5 minutes.
Pour the thick custard into a bowl, cover with clingfilm and leave to cool completely.

For the Cake:
225g soft butter / margarine
225g caster sugar
4 eggs
225g plain flour
1 tsp baking powder
2 tbsp milk

Preheat the oven to 180 degrees C / 350 degrees F / Gas 4
Grease and line two 20cm round cake tins.
Whisk all the ingredients together using a stand mixer or electric hand mixer til pale and fluffy.
Divide equally between the tins and smooth the tops using a spatula.
Bake for 20 - 25 minutes until golden brown and springy to touch.  Cool on a wire rack.

For the Buttercream:

50g soft unsalted butter
150g icing sugar
2 tbsp vanilla creme patissiere
1 - 2 tbsp milk if needed.

Cream together the butter and icing sugar.  Beat in the creme patissiere and enough milk to get a smooth spreadable consistency.

To assemble:

Place one cake layer flat side up on your serving plate.  Spread over the vanilla creme patissiere then top with the second cake layer, flat side down.
Spread a small amount of buttercream over half the biscuits and sandwich with the other half.  Stick the biscuits around the edge of the cake using a tiny dab of buttercream.
Spread the remaining buttercream over the top of the cake and crumble over any extra biscuits (or just eat them yourself!)