REMOVE THE SKIN FROM THE FILLET, if necessary, and go over the fillet carefully with your fingers to remove any small bones. Wash and pat dry with paper towels. Grill the fish for 3 to 4 minutes on a side, depending on thickness, turning gently. The fish should still be slightly translucent in the center since it will continue to cook after being taken off the grill. While the fish is grilling, boil down the marinade until it is reduced by half. Spoon a few tablespoons over each portion of fish. Serve immediately. Note: The fish may also be served at room temperature or chilled.