In a glass baking dish, whisk together soy sauce, lemon juice, mustard and pepper. Add salmon; turn to coat completely. Cover with plastic wrap and then marinade in the refrigerator for 30 minutes.
Preheat oven to 375 degree F. Grease a 9X13-inch glass baking dish.
Drain salmon from marinade and then place in the prepared baking dish. Spread strawberry jam evenly over fillets.
Bake, uncovered, for 15-20 minutes or until salmon flakes easily with a fork.
Serve with salad or any steamed vegetables.