Yes you most certainly can. LA Muscle have designed several supplements specifically for this goal.
You basically have two choices. You can either take one or several supplements from the Muscle Gain category (such as Norateen Heavyweight II) and one or several from the Fat Loss category (such as Fat Stripper) at the same time. Or you can take specific supplements which have been designed to help you lose fat and gain muscle at the same time such as Sculpt.