Toss the fresh mint leaves into a food processor or blender along with the salt, garlic and nuts. (Pine nuts are good; walnuts are okay also.) Start the food processor and then slowly add olive oil. Don't process too long or add too much oil; aim for a consistency that can be spread with a knife. When done processing, remove it to a dish and stir in the cheese. This is great spread across the top of broiled salmon or halibut fillets. You can also toss it with pasta as a simple side dish, or add broiled or steamed slices of chicken, seafood, or vegetables to make a main dish.