Preheat oven to 350 degrees. Line a regular muffin pan with paper liners. This will make 16 cupcakes filling each about 3/4 full. In a large mixing bowl, combine marzipan, butter, sugar and eggs, then beat until creamy. In a large wire strainer or a sifter, combine flour and baking powder. Remove bowl from mixer and gradually sift mixture into marzipan mixture, folding while sifting. Stir in crushed pineapple and vanilla until blended. Evenly fill the muffin cups with the batter and bake for about 25 minutes, checking with a toothpick before removing. Remove from oven and place pan on a wire rack for about 10 minutes to cool, then remove cupcakes to wire rack and cool completely. Mix chocolate and butter in a small saucepan, over low heat, until melted and smooth. Spread some glaze over tops of each cupcake. Sprinkle with a little brown sugar and top with a pineapple tidbit.