Beat together the butter, sugar, vanilla and eggs in a mixing bowl.
Sift in the flour and baking powder. Fold together until a runny batter forms.
Line a baking sheet with 12 cupcake cases and fill with the batter.
Bake in an oven at Gas Mark 4 for 20 minutes until golden.
Meanwhile, chop the white chocolate in to small pieces and place in a glass bowl.
Bring the cream to the boil in a saucepan.
Pour the cream over the chocolate and stir as the chocolate melts.
Leave to thicken in to a thick ganache. This may take about 15 minutes. Keep stirring to make sure it doesn't thicken too hard.
Cut a well in the centre of your cupcakes and fill with cranberry sauce. Place the top back on.
Place the ganache in an icing bag and carefully ice the top of your cakes.
Sprinkle with red edible glitter and top with silver balls.