If you are making baked potatoes in the microwave, you should cook each side for about 4 minutes. Check to see if they are done by inserting a knife or fork and if it slides in and out easily it’s done. If not, cook each side for an additional minute. If you are making your potatoes in the oven, try cooking them for 20 minutes then check to see if they are done. If not, cook them for about 3 more minutes and check again.