Baked potatoes that have been cut into slices or wedges, 5-10 minutes on the grill. How To Make A Baked Potato. Conventional Oven Baked Potatoes: Wrap the potato in foil, poke it with a fork 5 times for venting, and bake it in the oven for 45 minutes at 400°.ow Long To Microwave Baked Potatoes. To make a microwave baked potato, cook it on high heat for 2-4 minutes per side. The time will vary, depending on the power of your microwave and the size of the potato.