For the perfect roast potatoes, you have to boil them first. Add your halved peeled potatoes to a big Le Creuset Shallow casserole, cover in cold water and add a generous pinch of salt.

Let them come to the boil with the lid on and simmer for 15 - 20 minutes until a knife goes through them easily but not so they fall apart. Preheat your oven to 200C° (180C° Fan Forced).

Drain your potatoes and in the same pot while its still hot add half of your butter and olive oil, and season well as it starts to melt together add your potatoes back to the casserole and close the lid and jiggle them about to push against each other and sides of the pot creating rough edges to the potatoes and coating in the butter and seasoning at the same time.

Add rosemary and remaining butter, season again, sprinkle in the polenta to coat and roast without the lid for 40 - 50 minutes tossing every now and then for an even crispy potato edge. Sprinkle with grated parmesan to serve and eat while hot.