Using a mixer, cream together the softened butter and cream cheese. Beat for 3 minutes until fluffy and pale yellow in color.
Add the vanilla, lemon extract and lemon zest, beating just until combined.
Lower the speed of the mixer, and begin to add the powdered sugar, alternately with the thawed pink lemonade concentrate. Stop and scrape the sides of the bowl periodically, so all of the ingredients will combine.
Add a few drops of red or pink food coloring.
After all of the ingredients have been added, increase the speed of the mixer and beat for 2-3 minutes until fluffy and no lumps remain.
6 cups to frost: 36 cupcakes, one 3 layer  inch layer cake, more than enough for a standard 13 x 9 sheet cake