Yes you can. And you should refridgerate them. However, do not be surprised to find that they have turned brown. They will still be edible though.
I wouldn't recommend having a marinade on potatoes overnight. You can cut your potatoes up the night before and have them soak in water to avoid turning them brown/black. Just make sure the water is about an inch over the potatoes. If you want to marinate, an hour of soak time is good enough for potatoes. It's the oxygen that is touching the potatoes that turns them, so there might be some areas of the potato not completely covered in oil. If you still want to try it, make sure to have an airtight lid on.
Yes, it is okay to cut up sweet potatoes ahead of time as long as they are stored properly in the refrigerator to prevent them from spoiling.
It isn't recommended to cut the potatoes a few days before cooking. As soon as they are cut, the air will hit it and turn the insides brown (like an apple). You can cut them the night before and soak the potatoes in water until ready to cook.
No, they don't. That is how you can preserve peeled potetoes overnight, by putting them compeltely in water in the fridge.
you put cut up potatoes and fry them in a pot of oil.
This is not a good idea, you'd get bad results. If you want good roasted potatoes, take some new potatoes and boil them for 20 minutes just until they are slightly tender, not til they are fully cooked. You can let them cool, cut them up into pieces, and refrigerate overnight. Next day, pull them out, put them in roasting pan, sprinkle with a little olive oil, salt and pepper, and roast them at 500 degrees for half an hour. They're the bomb!
You can soak the peeled and cut potatoes for up to 24 hours prior to boiling.
no they will not turn brown
No, both are equally healthful. It's what you put in the mashed that will make it unhealthy or not.
They aren't grown.The potatoes used in them are grown,and then cut up and fried.
Roasting red potatoes works just as well as roasting any other type of potato.
Cut the potatoes into approx. 1 inch cube. If you do this they should only need to boil 15 minutes. If you have the pieces bigger, then it will take longer.