Heat Oven To 375 Degrees F. In 10-Inch Skillet, Cook Beef Over Medium Heat, Stirring Frequently, Until Thoroughly Cooked; Drain. Stir In Barbecue Sauce; Cook 1 To 2 Minutes, Stirring Occasionally, Until Hot. Stir In Cheese. If Using Crescent Rolls: Unroll Dough; Separate Into 4 Rectangles. Press Each Into 8X4-Inch Rectangle, Firmly Pressing Perforations To Seal. If Using Dough Sheet: Unroll Dough; Cut Into 4 Rectangles. Press Each Into 8X4-Inch Rectangle. Cut Each In Half Crosswise, Making 8 Squares. Place About 2 Rounded Tablespoons Beef Mixture On Center Of Each Square. Fold Dough Over Filling, Forming Triangles; Press Edges With Fork To Seal. With Knife, Cut Small Slits In Tops For Steam To Escape. Place On Ungreased Cookie Sheet. Brush With Egg; Sprinkle With Sesame Seed. Bake 11 To 18 Minutes Or Until Golden Brown. Immediately Remove From Cookie Sheet. Serve Warm.