There is a grocery store in the south (the name starts with a P) that has the best tasting buttercream icing ever. This recipe is an attempt to duplicate their icing. Whenever I use this recipe on my cakes, everyone gives the cake rave reviews...
Combine dream whip, water, and vanilla with a mixer in a deep bowl until combined on low; Increase speed to high and whip until mixture begins to look fluffy (approximately 4 minutes).
Add shortening, whipping cream, and butter. Combine with mixer on low speed, scraping sides of bowl as needed. Once combined, mix on high for approximately two minutes. It should look like frosting at this point. Add powdered sugar, 1 cup at a time, mixing on low speed after each addition.
This recipe will frost a 13 x 9 x 2 or two 9" rounds, with icing left over for piping and decorating.