In a large mixing bowl, beat Powdered Confectioners Sugar (6 cup) on high speed for a few seconds to break up lumps.
Add the Cream Cheese (18 ounce), Salted Butter (8 tablespoon) and Vegetable Shortening (1/2 cup). Beat on low, gradually increasing speed. Continue to beat, scraping the sides, on medium speed for 3 to 5 minutes until smooth and creamy.
Beat in the Milk (1 tablespoon) and Vanilla Extract (1/2 tablespoon) and increase speed and beat for another 1 to 2 minutes until desired consistency and its ready to use.