Cook lasagna noodles according to package directions. Drain noodles; rinse with cold water. Drain again.

For filling, in a medium mixing bowl stir together egg, ricotta or cottage cheese, chicken, and 1-1/2 teaspoons tarragon or basil.

To assemble bundles, spread about 1/3 cup of the filling over each lasagna noodle. Roll up noodles, starting from a short end. Place bundles, seam-side down, in a 2-quart rectangular baking dish; set aside.

For sauce, in a medium saucepan melt the margarine or butter. Stir in flour, mustard, salt, and pepper. Add milk all at once. Cook and stir until thickened and bubbly. Gradually add cheese, stirring until melted after each addition. Pour sauce over lasagna bundles. Cover dish with foil.

Bake in a 375 degree F oven for 30 to 35 minutes or until heated through. Let stand 10 minutes before serving. Transfer bundles to individual plates. Stir sauce in baking dish. Spoon some of the sauce over each bundle and, if desired, sprinkle with paprika or parsley. If desired, garnish with fresh tarragon sprigs. Makes 8 main-dish servings.

Prepare lasagna rolls. Cover and refrigerate up to 8 hours. Continue as directed.