In a stand mixer, mix all the ingredients for 9-12 minutes with hook and low speed until get a elastic, smooth and soft dough. Shape it to a large ball and cover with wet cloth. Set aside for proofing (around 1 hour).
When the dough is about 1.5 times or double in size, transfer out and re-knead until smooth in surface again (key step to smooth surface). You can finish use the slowest speed of stand mixer and mix for 2 minutes until it turns smooth again.
Prepare your well kneaded dough and pre-cleaned Lop Cheung. Break the lop Cheung into halves.Divide the dough into 6 portions and then shape each one into a long strip (around 30cm long with smaller ends). Then wrap the strip around the sausage. Finis all of them and place on baking papers (cut into 10cm long and 5 cm wide).
Place in steamer, covered and set aside for 15 -20 minutes for second proofing. Steam 20 minutes over high fire after the water boils. Enjoy when still warm. If you make a larger batch, you can freeze the steamed buns after cooled down completely.