Marinate cut fish fillets with turmeric, corn starch, salt, black pepper for at least 30 minutes
In bowl #1, beat eggs and add milk. Mix well.
In bowl #2, mix 1/4 cup breadcrumbs and 1/4 cup corn meal
Dip fish into bowl #1 and then bowl #2 until completely covered. Repeat for all the fish pieces until done. Refill bowl #2 whenever necessary.
Heat 1.5 cups of oil in the wok to >300 degrees F.
Deep fry the fish fillets in batches 2-3 minutes per side. Set aside in serving dish and repeat until done.
In the wok with a little oil, stir fry the ginger, onions and garlic for about 2 minutes. Add ketchup, oyster sauce, fish sauce, sugar. Mix and bring to boil. Add 1/2 cup water if necessary to maintain liquid consistency.
Add sliced tomatoes and bell peppers. Mix and bring to boil. Simmer for about 5 minutes.
Pour sauce over fish and serve.