We feed them some grain mixed with a touch of sweet feed (about... a pound twice a day?) and then they are out in a green pasture most of the day. On days they don't get a whole day of grazing, they get 3-4 squares of grass hay.
I would say supplement the grazing/hay with a little grain. It doesn't need to be a whole lot, and it can be either both morning and evening or just one or the other. :)