I picked up a Sainsburys magazine tonight. I read a great suggestion in there for Christmas dinner. Par-boil your potatoes in advance. Freeze on a baking tray before putting into a freezer bag so they don't stick together. On the day just put your potatoes straight from the freezer into the hot fat and cook as normal, It's one less thing to worry about on the day and it says they come out crisper and fluffier this way. Mr BS doesn't really like roasties so this will be great for just cooking a few at a time for me.