Annie told me that it has long been a sorrow of hers that she can't fry potatoes. Being the grandchild of Grandma Rossi I know how, and I promised to tell her so that she could make potato tacos for the Hawaiian Guppies.
You'll need potatoes, oil, salt, pepper, a decent pan and a metal spatula. Your can add other flavoring ingredients, like onions and cumin (for tacos) or garlic and rosemary, but for breakfast I like them best plain. If you're in a big hurry you can start with cooked potatoes, but they'll turn out a lot better if you fry them from raw. Cut them up into thickish (~1/2cm) slices. If you're adding cumin and onion, your can have them start cooking while you wash and cut up the potatoes.
Next, stir the potatoes along with the salt and pepper (and rosemary if you're using it) around in a well-oiled (don't skimp! at least 2-3T of oil!), wide (12" is ideal), stick-resistant but not nonstick (a cast-iron skillet would be good) pan with a lid on medium heat. Turn the heat down to medium-low, put the lid on, and let the potatoes steam themselves for about 20 minutes. They should be all the way cooked at this point.
Turn the heat up to medium (if you want to add garlic, now's the time) and let the potatoes cook for a few minutes before stirring them around. You'll have to scrape them off the pan pretty hard, but you want to get the crusts up. You may have to add some more oil. Alternately cook and stir 3 or 4 times, till they look sufficiently browned and crusty.