To defrost the Sirloin, remove from the freezer and leave on your kitchen worktop for one day. Alternatively, place the Sirloin in the fridge and allow it to gently thaw for two days. Before cooking, remove the packaging and allow the joint to dry out and reach room temperature.
Preheat a fan assisted oven to 180C.
Pat the joint dry and then generously season the fat.
Take an oven proof pan and heat on the hob to a high temperature. Add the sirloin and roll the joint around in the pan until it is beautifully caramalised.
Place the pan into the preheated oven and roast for 20 minutes per kg.
Remove from the oven and leave to rest for 20 minutes.