Preheat oven to 350 degrees F.
Follow cookie dough mix package directions, adding butter and egg. Roll out dough and cut out desired shapes with cookie cutters or a knife. Transfer to a cookie sheet and bake until golden brown, about 20 minutes. Remove to a rack and cool completely.
In a stand mixer fitted with the whisk attachment, mix all ingredients until smooth. Spread icing over cooled cookies with spatula. Dry for 4 to 6 hours or overnight.
To decorate, use edible markers to stencil or freehand desired design. You can also tint the icing with food coloring and pipe it on the cookie. Either way, allow to set for 4 to 6 hours.
To assemble, first decorate a flower pot to your liking. Glue floral foam inside the pot. Place each cookie on a cleaned long wooden popsicle stick and arrange in a bouquet fashion. Add hard candies around the bottom of the bouquet pot, if desired.