My new Bismark tip I used to fill them.
The recipe I adapted these from is here
http://www.foodnetwork.com/food/recipes/recipe/0,,FOOD_9936_80619,00.html I used a different cake recipe, and I frosted them with sweetened whipped cream (dyed pink of course) The filling is basically the same recipe.
These turned out really good. Mascarpone cheese is like my favorite food in the world.
I look forward to making lots more filled cupcakes!