Preheat your oven to 200°c. Peel your potatoes and cut into medium chunks.
Place a large roasting tray in the oven adding enough olive oil to cover the bottom. Place in the oven and allow to get hot, this should take around 5 minutes. Whilst the oil is heating up, split the cloves of garlic from the bulb and crush lightly with the back of a knife leaving the skins on.
Take the tray out of the oven and carefully tip in the potatoes, garlic cloves and rosemary sprigs. Season well with salt and pepper, then carefully toss everything together. Place back in the oven for 45 minutes. Once really crispy, remove from the oven and serve with your Christmas roast.
These are the easiest and crispiest potatoes you will every try!