This may not be simple enough for you, but it is REALLY good.

In a saucepan, melt 1 stick of butter. Stir in 1/4 cup of soy sauce, 2 TBSP worchestershire sauce, , 1 TBSP crushed garlic and 2 TBSP country dijon mustard. Let this mix simmer for 15 minutes while the grill gets hot.

Take a fillet of salmon, with skin on, and spray or brush flesh side with olive oil. Place on grill flesh side down and cook for 4-5 minutes over fairly hot fire. Flip and place on piece of aluminum foil with edges curled up to catch sauce and keep it from falling on the fire. Brush sauce liberally over the flesh side, and cook, covered, 8 to 15 minutes, until flesh just begins to flake. Brush with sauce two or three times while cooking.

Serve with rice or new potatoes, and a nice salad, and you'll be a star.