Finalised Idea

PINWHEEL COOKIES

1. 185g butter @ room temperature (Down from 250g)
2. 120g brown sugar (Changed from caster sugar -> Brown sugar ; Down from 275g)
3. 1/2 tablespoon vanilla essence  (Down from 2 Tablespoons)
4. 1/2 tablespoon peppermint essence 
5. 1 egg
6. 375g plain flour
7. 1 1/2 baking powder
8. 1 3/4 tablespoon cocoa powder
9. Baking Paper

180ºC for 12 minutes

1. Beat butter and sugar together with an egg beater until fluffy
2. Mix in egg and vanilla essence
3. Sift in flour and baking powder + continue beating
4. Seperate dough into 2 halves. Mix chocolate and peppermint essence into one half.
5. Roll the both doughs into flat rectangles approx 2mm thick.
6. Place the chocolate layer ontop of the vanilla layer.
7. Roll the doughs carefully and wrap them in baking paper + put them in the freezer for about 10 minutes
8. Wash up during this time
9. Take out the dough and cut it into slices.
10. Bake them for 12 minutes at 180ºc.

End result :