Mix the softened butter and sugar together until you get a creamy consistency.
Beat in the egg and vanilla extract.
Sift in the dry ingredients and mix.
Add the dark chocolate into the dough in tiny pieces.
Chill the dough in the refrigerator for 15-20 minutes.
Seperate the dough in 7-8 equal pieces.
Put the big chunks of white chocolate in the middle of the cookie doughs.
Bake the cookies in a preheated 180C oven for 9 minutes.