I used a simple 'Quick Cake Mix' recipe from my ultimate Cake Decorating Bible (The Complete Book of Cake Decorating by Bridget Jones - not THAT Bridget Jones) - This has lots of handy modifications for using different sized tins etc, but for the Pinata Cake, here's what I did:
Grease up the inside of a pyrex bowl with butter and set the oven to 170C or gas 3.
Mix the following ingredients in a different(!) bowl:
- 225g margarine or butter
- 225g caster sugar
- 5 eggs
- 275g self-raising flour
- 1/2 tsp baking powder
- 1tbsp milk
Pour into the greased pyrex dish and pop into oven for just over an hour (check around an hour, it shouldn't take more than 1hr 15mins). Leave to cool (be patient!!)
Once cool, tip out of the bowl and trim the top (which is now the bottom..) so it stands flat on a cake board or plate. Carve the top 'lid' off and scoop out the middle of the cake to create an empty bowl within the cake shell. Fill with sweets/chocs of your choice, and then glue the lid back onto the cake shell with buttercream. Cover the rest of the cake in buttercream until completely covered and smooth, and add decorations (sprinkles and sweets in this case but it's totally adaptable).