Boil potatoes in salted water for 15 minutes until tender.
Drain potatoes and mash until smooth.
Heat oil in a deep fryer to 180°C.
Mix butter, coriander, and green chilli into mash and cool completely.
Fold crabmeats and lime juice into the cooled potato mixture.
Shape the mixture into 4 round patties with wet hands.
Fry patties for 3-4 minutes per side until golden-brown.
Drain cooked crabcakes on kitchen paper.
Cook noodles according to package instructions and place in a bowl.
Process dressing ingredients into a paste and toss with noodles.
Serve crabcakes over noodles and garnish with cress, chilli, and spring onion.