1.Prepare the dough by mixing flour, water, yeast, baking powder, and oil. Knead until smooth and let it rest for 30 minutes.
2.For the filling, mix oyster sauce, salt, MSG, light soy sauce, dark soy sauce, water, minced ginger, chopped green onion, diced onion, sesame oil, ground beef, egg, and 1 tsp flour.
3.Roll out the dough and cut it into circles. Place a spoonful of filling in each circle and pleat the edges to seal.
4.Prepare the flour water mixture by mixing 1 tbsp flour, 1/2 tbsp starch, 1/2 tsp baking powder with 1 cup of water.
5.Steam the dumplings over boiling water for about 15-20 minutes. Serve hot with the flour water mixture.