Clean the fish fillets properly.
In a wide bowl, mix together the olive oil, chili powder, pepper powder, turmeric powder, lemon juice and salt, until a smooth paste.
Apply that masala paste over the fish fillets until well coated and set aside for one hour at room temperature or in the refrigerator.
Meanwhile, preheat the oven to upper grill mode and grease the grill pan with non-stick spray or butter to prevent the fish from sticking.
Then place it in the preheated oven and grill for 10 minutes then flip the fillets and again grill for 8 more minutes or until the fish cooked all the way through.