Roast potatoes - I like to parboil them first. So, peel and chop, into pan of cold water. Bring to the boil and cook for 5 to 10 mins once boiling. Drain, return to pan, put lid back on and give them a shake to roughen up the surface. Then into preheated roasting tin and coat with oil. Coook in oven for about 45 minute.
I usually do carrots and parsnips too, but don't parboil those, just chop and put in tin with oil and roast for 30 to 40 mins.