1. Prepare and bake 24 mini cupcakes. Allow to cool completely.
2. In a small bowl, dissolve the salt in hot water.
3. In a large bowl combine water, marshmallow fluff, shortening, icing sugar and vanilla. Mix well.
4. Prepare a piping bag with a 1A tip. Scoop the filling mixture into the bag, squeeze out the air and twist closed.
5. Insert the tip of the piping bag into the center of each cupcake and squeeze filling into the cake.
6. Use a piping bag with a 1M tip to frost each cupcake.
7. Dust with pink sprinkles and top with candy hearts.