In a large bowl add all the ingredients listed under marination and mix it well so that the fish pieces gets coated with the flour. Keep it aside.
Heat a 6-7 tbsp of oil ior enough to fry the fish in a skillet/thick bottomed pan on medium heat. Slowly add the coated fish filet in batches.
Fry the fish for a couple of minutes, until it turns crispy and brown. Transfer the pieces on kitchen towel, to remove excess oil. Keep aside for a while.
In a small bowl mix all the ingredients listed under sauce and keep it aside.
Now from the same skillet reduce the oil in which we fried the fish and keep just 1 tbsp of oil in it. Heat the oil on medium, when hot add the freshly grated ginger and saute for 1-2 minutes until the ginger turns slightly golden brown.
Next toss in the spring onions, garlic, chillies and saute for another 2 minutes on medium heat.
Pour in the sauce and mix everything well. Cook for a minute.
Finally add in the fried fish along with the julienned ginger and toss it well with the sauce.
Remove from heat, and garnish with coriander leaves. Serve it hot as an appetizer or as a side with some rice.