Fill up a pot of water and bring it to a boil. Put the egg noodles in to cook for 5 minutes or until al dente.
Drain, then run under cold water to slow down the cooking process and let it drip dry in a colander.
Use a mortar and pestle to pound the peppercorns until they've all split open. Leave them aside for later.
Lightly coat the crab pieces in potato starch, then heat up a pot of oil until hot and add the crab pieces in. Leave the carapace (the head or lid of the shellfish) out of the frying.
Let the pieces cook for 5 minutes or until just starting to cook.
Transfer them into a bowl for later.
In a wok or pan, turn the heat up to high and pour 4 tbsp cooking oil in. Lower the heat to medium and add the noodles in, spreading them out across the surface of the pan or wok.Note: The thinner the noodle layer, the quicker it will cook and crisp up. Let it sear for 5 minutes or until crispy on the underside, then flip and repeat the searing until both sides are a golden brown. Transfer onto a serving plate.
Heat up the wok on high heat again and pour 2 tbsp oil in, followed by the butter. Turn the heat down to medium and throw in the onion and garlic. Let it cook for 2 minutes.
Season the aromatics with the salt, sugar, crushed black pepper and chicken bouillon powder.
Bring the heat up to high and pour the water in.
As soon as the sauce boils, add the cooked crabs in and give them a toss until every piece is coated. Let them cook for another 5 minutes or until just cooked.
Add the long spring onion segments into the sauce to cook for 30 seconds.
Transfer the cooked crabs and sauce onto the noodles then garnish with the coriander and chopped spring onions.
Serve immediately as is!