* Salmon steaks may be either fresh or frozen. ~- Thaw salmon steaks, if frozen. Preheat a 6 1/2-inch microwave browning dish on 100% power for 3 minutes. Add cooking oil to the browning dish; swirl to coat the dish. Place fresh or thawed salmon steaks in the browning dish. Micro-cook, covered, on 100% power for 30 seconds. Turn the salmon steaks and micro-cook, covered, on 50% power about 3 minutes or till the salmon flakes easily when tested with a fork. Let the salmon steaks stand, covered, while preparing the wine sauce. For the wine sauce, in a 4-cup measure micro-cook the butter or margarine, uncovered, on 100% of power for 45 seconds to 1 minute or till melted. Stir in the cornstarch and white pepper. Stir in light cream. Micro-cook, uncovered, on 100% power for 2 to 3 minutes or till mixture is thickened and bubbly, stirring every minute. Stir Half the hot cream mixture into the beaten egg yolk. Return all to the 4-cup measure. Micro-cook, uncovered, on 50% of power for 1 minute, stirring every 15 seconds. Stir till mixture is smooth. Stir in dry white wine. Transfer the salmon steaks to a serving platter. Spoon the wine sauce atop. Garnish with seedless green grapes, if desired.