For these cookies I made last year, I used Betty Crocker sugar cookie mix and followed the instructions for roll-out dough. Using Betty Crocker is questionable for some vegans, so if you have any info on the source of the ingredients, or have a fool proof roll out cookie dough recipe, I'd appreciate the feedback. For Christmas I use the low-fat gingerbread recipe from my copy of The Joy of Cooking and veganize it.
The icing is basic buttercream: 2 sticks Earth Balance, 1 lb. powdered sugar, a tb. Silk Vanilla, vanilla-adjust quantities for consistency-whip and chill. I put the icing into bowls and tinted it with food coloring drops. I used mini tubes of writing icing for detail, but you could thin some buttercream and use it from a piping bag.
Happy Halloween :D