Cream Filling for Donuts

2 teaspoons very hot water
rounded 1/4 teaspoon salt
2 cups marshmallow creme (one 7-ounce jar)
1/2 cup shortening
1/3 cup powdered sugar
1/2 teaspoon vanilla

Combine the salt with the hot water in a small bowl and stir until salt is dissolved. Let this mixture cool.

Combine the marshmallow creme, shortening, powdered sugar, and vanilla in a medium bowl and mix well with an electric mixer on high speed until fluffy.

Add the salt solution to the filling mixture and combine.

Using a cake decorator or pastry bag, inject each donut with filling.