Preheat oven to 200 degrees. Roughly chop the Manner wafers, melt the butter and let cool. Mix flour with sugar, vanilla, salt and baking powder. Whisk butter, eggs and milk, then slowly stir in the flour mixture. Then mix the coarsely chopped wafers into the batter.
Place paper baking cups into a 12 muffin tin and fill cups with batter. Bake at 200 degrees about 20 minutes.
If you like, decorate the luke-warm muffins with melted chocolate.