In a large mixing bowl, beat together the shortening and butter with the paddle attachment of an electric mixer until light and fluffy. Beat in vanilla.

Gradually add sugar, one cup at a time, beating well on medium speed. Scrape sides and bottom of bowl often.

Gradually add milk; beat at medium speed until light and fluffy.

Remove one quarter of the icing to a separate bowl. To the larger amount of icing, add one drop of desired petal color and beat until thoroughly mixed in. Add additional color, one drop at a time, until desired color is achieved. Repeat with the smaller bowl, using desired flower center color.

Fit #104 petal tip into one of the disposable decorating bags. Snip off the tip of the bag. Fill the piping bag halfway with petal icing. Hold the piping bag at a 45? angle to the surface of the cupcake, with the wide end toward the outer edge and the narrow end at the center. Gently squeeze out some icing, and move the piping tip toward the outer edge of the cupcake, then back in toward the center to create a narrow petal. Repeat all the way around the edge of the cupcake.

Fit #2 tip into the other disposable decorating bag. Snip off the tip of the bag. Fill the piping bag halfway with the other color of icing. Hold the piping bag at a 90? angle to the surface of the cupcake, gently pipe a circle of small dots in the center of the cupcake, over the top of where the petals meet.

Cupcakes can be stored at room temperature for up to 3 days.