Place frozen dough on greased cookie sheet and rub with vegetable oil. Cover with a damp cloth or plastic sheet and let rise in a warm, draft-free place (75° to 85°) until dough is 2 1/2 times original size (about 4 hours.) Whip cream cheese in a small bowl until light and fluffy, then add ricotta cheese and chopped onion and mix well. Set aside. Sauté ground beef with salt and seasoning in frying pan and drain well. Add tomato sauce and set aside. Roll out dough on a floured surface, shaping into a 12-inch square. Spread with cheese mixture, leaving a 1-inch edge of dough on the fat side of the square. Cover cheese layer with chopped spinach. Then top with beef mixture, spreading evenly. Using a long spatula for support, roll up the dough sheet into a log shape, sealing the dough edge with fingers. The roll will be heavy and full. Cut in half to make 2 logs and place both pieces on a well-greased cookie sheet, seam side down, tucking under the log ends to keep in the filling. Brush with beaten egg and sprinkle with sesame seed. Bake at 350° for 35 minutes. Cool at least 15 minutes before serving.