Bake sugar cookie dough according to package directions; let cool completely.
In a large mixing bowl stir together confectioners sugar, meringue powder, and cream of tartar. Add the water and vanilla. Beat with an electric mixer on low speed until combined. Beat on high speed for 7 to 10 minutes or until icing reaches a stiff piping consistency.
Transfer 1/2 cup icing to a small bowl. Tint the 1/2 cup icing black.
Transfer 1/4 cup icing to a separate small bowl. Tine the 1/4 cup icing orange.
Spoon the orange and black icing into separate freezer weight ziptop bags and seal. Snip a very small corner from each of the bags. Using the black icing, pipe black dots onto each marshmallow for the eyes. Using the orange icing, pipe a short thin vertical line for the nose. Let dry for at least 30 minutes.
Stir 2 to 4 tablespoons warm water into the remaining white icing until icing reaches a thin spreading consistency. Pipe or spread icing in a puddle shape on each cookie.
Pipe a thin line of black icing on each side of the cookie to create the "stick" arms. Use a toothpick to drag the black icing to create the tips of the sticks.
Place a marshmallow at the top of each cookie, on top of the icing. Place 3 miniature chocolate pieces, tip side down, down the middle of the cookie for the snowman's buttons.
Wrap a fruit leather strip around the marshmallow for the scarf.