Leftover new potatoes? That’s a reason to get out the frying pan and start sizzling.
The kindest thing you can do to leftover potatoes is to keep them dry while they wait in the fridge for their call to the kitchen. Moisture makes them slimy, and wet potatoes won’t sizzle, they’ll steam. Ensure they are dry before putting them in a container (pat with paper towels if necessary), and choose a wide rather than deep container so they can dry off even more while in the fridge. The trick is to cover them loosely with paper towels. If they are in a plastic container, don’t cover them with a lid because moisture will be trapped and it will form on the lid and drop back on to them at that very moment you remove the lid before cooking them. Annoying! Paper towels are all you need, draped over and gently tucked around the potatoes. They’ll keep well for 2-3 days.
Bring them to room temperature before frying. Chop them into rough pieces, heat a frying pan (skillet) over medium heat and drop in a nice big fat lump of butter and watch it sizzle. Then add the potatoes and cook them at a moderate heat (that means, not so hot the butter starts browning, but not so slow that the potatoes sit their absorbing the butter instead of crisping) and cook, stirring often, until golden. You can get all fancy and lift the frying pan in one hand and give a quick toss, and with a bit of luck the potatoes will all end up back in the pan. Otherwise, follow the 2-second rule, or whistle in the dog.