Chop up spuds, boil for 5 mins, then drain them in a metal drainer, and chuff them up (bounce them around in the drainer till all the potatoes are kinda fluffy on all the edges). Heat duck/goose fat in the roasting tin for a few mins, then put the chuffed up potatoes in, with some sea salt and rosemary, make sure they're all coated in the fat with a pastry brush. Put in to roast for about 90 mins on high heat, turn once. Lovely.
Parsnips - cut them up into slices no more than a couple of cm's thick, coat in honey and put some fresh rosemary in, add some olive oil to roast in and roast for about the same time, lush.