Here are two signature recipes for icing that have been passed around Home Cake Decorating Supply Co for many years.
They mention meringue powder and icing base, both of which are available to purchase at the shop.
3 level tablespoons meringue powder
4 cups powdered sugar (half of a 32 ounce bag)
5-6 tablespoons of water
Beat on high for 5 to 6 minutes to get stiff icing.
Thin down carefully with a little water for icing cookies.
NOTE: 4 ounces of meringue powder makes 4 recipes which equals 12 cups of icing.
1/2 cup Icing Base
2/3 cup of hot water
2 lbs. powdered sugar (about 8 cups)
2 cups Crisco shortening
1 teaspoon clear vanilla
1 teaspoon almond flavoring (optional)
1 teaspoon salt
Mix base and tap water until dissolved.
Slowly add powdered sugar.
Beat until smooth.
Add Crisco, vanilla, flavoring (if desired) and salt.
Beat on high for five minutes.
Light, fluffy and delicious!