I used to do this by opening a tube of store-bought cookie dough and squishing it flat in the shape of a circle. Baking it for 20 minutes then decorating. You can still do it that way.
Now, because it tastes so much better and because of the allergies of our youngest two, I do it the homemade way. A few more steps but worth the effort.
I make a double batch of Flax-Oatmeal Cookie dough. (This recipe minus the coconut and nuts + egg substitute in place of eggs).





and it always turns out good!