PREHEAT oven to 350°F. Mix tapioca, salt, pepper and milk in saucepan. Let stand 5 minutes. Cook on medium heat until mixture comes to boil, stirring constantly. Add butter; stir until melted. Remove from heat; cool slightly.
MEANWHILE, beat egg whites in small bowl with electric mixer on high speed until stiff peaks form; set aside. Beat egg yolks in large bowl with electric mixer on high speed until thick and lemon colored. Gradually add the tapioca mixture, beating on medium speed until well blended. Gently stir in egg whites.
HEAT greased 10-inch ovenproof skillet on low heat. Add egg white mixture; cook 3 minutes. Place in oven.
BAKE 15 minutes or until knife inserted in center comes out clean. Make cut in center of omelet, being careful to not cut all the way through to bottom of pan. Carefully fold omelet in half; turn out onto serving platter. Cut in half to serve.