CREPES: Combine all ingredients in a blender; blend for 1 minute. Scrape down sides and blend for another 15 seconds or until smooth. Refrigerate at least 1 hour. Heat a lightly oiled griddle, skillet or crepe pan. Pour or spoon 3-4 tablespoons of batter in pan and spread out to form a round, 6-inch crepe. Brown lightly on one side only. Stack crepes between layers of waxed paper and set aside until ready to be filled and rolled (Makes 16 crepes.)
FILLING: Melt 2 tablespoons butter in a large saucepan. Add shallots and mushrooms; sauté until limp. Stir in remaining butter until melted. Gradually add flour, one tablespoon at a time; cook and stir until bubbly. Gradually stir in broth, cream, and wine or chicken broth. Cook over medium heat until thickened. Add chicken, crabmeat, Parmesan, rosemary, and salt; mix well. Assembly: Preheat oven to 400° F. Fill crepes browned side down and roll, placing them seam side down in a buttered 9x13-inch baking dish. Top with Swiss cheese and bake 20 to 30 minutes. Garnish with parsley.