The bismark tip (the long filling tip) is cool, but if your filling is thick it can be a pain to use.. and if it has chunks in it forget it. I just use a #12 round tip. Stick it in the center angled towards the outside of the cupcake and squeeze a little.. pull up and move the tip angle to a different side and squeeze a little more. I do it three times.. it helps to get the filling in more places. I love filled cupcakes.. White cake with raspberry puree in side iced with lemon BC is really good.. Chocolate cake with chocolate mousse inside and chocolate ganache on top.. MMMMM.