Mix all ingredients, except for the chocolate bunny, and use the mixer on the highest setting to make a smooth dough.
Place the chocolate bunny between two layers of cling film and crumble into small pieces with a hammer or meat tenderizer. Carefully fold the chocolate chips into the batter.
Fill the batter into 18 muffin cases. Always stir well when scooping out the dough bowl, as the chocolate pieces quickly sink to the bottom.