In a large skillet cook turkey or turkey sausage and onion until meat is browned, stirring to break up meat. Drain off any fat. Stir in cream cheese until combined; add mushrooms. Set aside.

For crust, lightly grease a 9-inch pie plate. Unwrap biscuits and separate. Arrange biscuits in pie plate, pressing onto the bottom and up sides of the plate, extending biscuits about 1/2-inch above pie plate. With kitchen scissors, cut edge of biscuits at half-inch intervals, if desired. Spoon turkey mixture into shell, spreading evenly.

In blender container or food processor bowl combine egg, cottage cheese, and flour. Cover and blend or process until smooth. Spoon over turkey mixture. Bake, uncovered, in a 350 degree F oven for 25 to 30 minutes or until edges are browned and filling is set. Let stand 5 to 10 minutes before cutting into wedges. Garnish with tomato and chives, if desired. Makes 6 main-dish servings.

If using ground turkey, add 1/4 teaspoon salt and 1/4 teaspoon pepper to meat mixture.