Saturday night we treated ourselves to steak on the grill, a nice sirloin from Bostrom's Farm. This treatment for steak comes from Alice Waters, described in her book The Art of Simple Food (a great cookbook, by the way, with lots of discussion of simple technique). You can use a variety of herbs depending on what you have available; a mixture is nice. I used oregano, parsley, and basil from my garden. Rosemary and marjoram work well, too.
Salt (about 1 1/2 tsp per 2 servings of steak)
Pepper to taste (be generous)
Finely chopped fresh herbs (about 3 Tbsp for every 2-3 servings of steak)
About an hour before you plan to grill, take the steak out of the refrigerator.
Combine the salt, pepper, and herbs with a teaspoon or so of olive oil (just enough to form a bit of a paste that you can spread. Spread it all over the steak and let sit for an hour.
Cook the steak over a hot fire to your desired degree of doneness (about 8-10 minutes total cooking time for medium rare). Keep in mind that grassfed beef is best when not too well done because it has less fat in it.