Place onion and margarine in a 2 cup glass measure, Microcook, uncovered, on 100 percent power ( high) about 1 minute or until tender. Stir in crumbs, parmesan cheese and nuts. Peel tomatoes, if desired.
Cut into 1/2 inch slices. In a 9 inch microwave safe pie plate, arrange tomato slices. Sprinkle with Worchestershire sauce. Cover with wax paper. Cook on high for 2 to 3 minutes (low wattage ovens, 2 1/2 to 3 1/2 minutes) or until almost heated through. Give plate a half-turn once. Sprinkle crumb mixture over tomatoes. Cook, uncovered on high 30 to 60 seconds (low wattage ovens 1 to 2 minutes) or until heated through.
Each Serving: 128 calories, 4g Protein, 14g Carbohydrates, 7g Fat, 2mg Cholesterol, and 202mg Sodium.