House Buttercream

6 c. confectioner's sugar

1/2 tsp. salt

1 tsp. vanilla extract

1 c. boiling water

2 3/4 c. shortening

1 1/2 sticks butter, slightly chilled and cut into 1 inch pieces

In bowl, stir together sugar, salt and vanilla.  Add and whip at low speed the boiling water.  Let cool.  Add and whip until smooth the shortening and butter.  Increase speed to med-high and whip until light and fluffy and doubled in volume.  This should take 10-20 min.