Butter bottom and sides of 2 quart souffle dish or casserole. Dust with Parmesan cheese. In medium saucepan, combine soup, salmon, 2 tablespoons Parmesan cheese and lemon peel. Cook and stir over medium heat until mixture is hot. Remove from heat. In small mixing bowl, beat egg yolks at high speed until thick and lemon colored, about 5 minutes. Wash and dry beaters. Blend a small amount of hot salmon mixture into yolks, then stir warmed yolk mixture into salmon mixture. In large mixing bowl, beat egg whites and cream of tartar at high speed until stiff but not dry, just until white won't slip when bowl is tilted. Gently and thoroughly fold yolk mixture into whites carefully.
Pour into prepared dish. For a "top hat" hold a spoon upright and circle mixture to make ring about 1 inch from side of dish and 1 inch deep. Bake at 350 degrees until puffy, delicately browned and souffle shakes slightly when oven rack is moved back and forth, 35 to 40 minutes. Serves 6.
