I read your Q and A about washing the potatoes and putting them in the oven the night before a work lunch. Would you poke them the night before or in the morning before turning the oven on? Just worried about getting gray streaks through my potato.
I would just skip poking the potato all together. It is very rare that a baked potato will burst if the steam can’t escape. The two most common examples when you would need to poke them are, in the microwave (we always recommend pricking the potato with a fork so steam can dissipate into the oven cavity) or if a potato goes from refrigeration and is cold when placed into a hot 400 degrees F oven. Quite often I forget to pierce the skin before placing in the oven. You asked an excellent question, poking or piercing the potato too far in advance will result in discolored or gray where the utensil went into the potato.
If doing for the next day, I’d probably just wash the potatoes and leave on the counter, covered with a clean towel. In the morning I’d turn on the oven to 400 degrees F and put the potatoes directly on the racks. Then go shower, do make-up, get dressed, have a cup of coffee or a glass of juice and by that time you should start to smell the aroma of a fully baked potato. It takes about one hour (or less if you have a convection oven instead of a conventional oven) and if using an oven thermometer it should be a minimum of 185 degrees F, is fully cooked at 210 degrees F. You can often just heat it up a minute or two in the microwave at work. For other baked potato tips, check out “All Things Baked Potatoes".