chocolate sandwich cookies

Had friends over this weekend, that have lived in the states, and was missing it a bit. So I decided to make these lovely little things, that I had invented a few months ago, they are a cross between woopie pies and oreo cakesters.
They where a big hit, and I would have to say, that I was being extremely good diet wise and did only have one :)


Cookies:

100ml Yogurt Natural

6 tablespoons cocoa powder
75g margarine
200g sugar
1 egg
1tsp vanilla sugar
½tsp bicarbonate of soda
½tsp fine salt
125g plain white flour

Filling:
100g cream cheese
300g icing sugar

Preheat oven to 175°C/350°F/Gas Mark 4.
To make the cookies, cream together the margarine and sugar in a bowl, add the egg and mix well, for a few minutes.
Mix in the Yogurt.
Add all the dry ingredients and mix well.
Drop small blobs (2 teaspoons) of dough onto a baking tray lined with parchment paper, spacing them 2 inches apart.
Bake until the edges of the cookies spring back when lightly touched (7 to 9 minutes).
Transfer to wire racks and allow to cool.
To make the filling, mix together the cream cheese with half of the icing sugar, then add the other half of the icing sugar and mix well.
Split your batch of cookies in half and pipe or spoon 1-2 teaspoons of the filling onto the flat sides of one half of your batch. Sandwich with the other half of the cookies, pressing the flat sides to the filling.

have also tried freezing them, and they are great to have in the freezer to take a few out and thaw when you feel like a snack, but also good frozen almost like an ice cream sandwich.
(I used dairy free margarine, lactose free yoghurt and have a nice cold glass of lactose free milk with them).