Prepare the pork filling: Add 230g pork mince, 1 tbsp light soy sauce, 1 tsp dark soy sauce, 1 tsp oyster sauce, 1/2 tsp white pepper powder, 1/2 tsp ginger powder, 1/8 tsp five spice powder, 1/2 tbsp finely chopped spring onion and 1 egg into a medium bowl. Mix for 2–3 minutes in one direction until the filling becomes slightly sticky and cohesive.
Prepare the bowl: Lightly grease a medium heatproof bowl with a small amount of cooking oil. Spread a thin layer of the pork filling evenly across the bottom of the bowl.
Add the dumpling wrapper layer: Place 1 dumpling wrapper on top of the pork layer and gently press it so it sticks to the filling and sits flat.
Continue building the layers: Spread another thin layer of pork filling over the dumpling wrapper. Place another dumpling wrapper on top. Repeat layering pork filling and dumpling wrappers until the bowl is almost full, leaving about 1–1.5cm space at the top.
Finish with a dumpling wrapper: Place a dumpling wrapper as the final top layer. Pour 2 tbsp water evenly over the top wrapper to keep it moist during steaming.
Steam the dumpling lasagna: Bring water in a steamer pot to a full boil. Place the bowl into the steamer, cover with a lid and steam on high heat for 20 minutes.
Remove and garnish: Carefully remove the bowl from the steamer. Sprinkle 1/2 tsp white sesame seeds and 1/2 tsp finely chopped spring onion on top, then drizzle 1 tbsp chilli oil evenly over the dumpling lasagne.