Method: 

1. Cut the lime in half. Set 1 half aside. Cut the other half into wedges and set aside.
2. In a medium bowl, mix together the mango, bell pepper, and purple cabbage. Set aside.
3. In a separate medium bowl, add the iceberg lettuce and squeeze in juice of ½ a lime. Toss to combine and set aside.
4. In a medium cast-iron pot (preferably a Dutch oven), heat the oil over high heat until it reaches 350°F.
5. While the oil heats up, prepare your fish. Place the panko breadcrumbs on a large plate.
6. Pat the fish fillets dry with a paper towel. Use a bamboo skewer to skewer through the center of the fish—this ensures that the fish does not curl up while frying.
7. Rub each fillet with 1 teaspoon oyster sauce. Lightly sprinkle 1 tablespoon tempura mix and 1
   tablespoon cold water on each fillet all over. Take 1 fillet and place on top of the panko breadcrumbs. With the help of a spoon, cover the fillet with breadcrumbs, lightly patting the filet to ensure the breadcrumbs stick. Repeat with the 2nd fillet.
8. Once the oil has reached 350°F, carefully lower the fillets into the pot and fry for about 2–3 minutes, until golden brown. Remove from oil and place on a wire rack or a paper towel-lined plate.
9. Heat a medium cast-iron or nonstick pan over medium-high heat. Once hot, place each tortilla into the dry pan and warm for about 20–30 seconds on each side.

To assemble tacos: 

Arrange the warmed tortillas on a plate, using the lime wedges to help prop them up. Divide the shredded iceberg lettuce between the tortillas. Place 1 piece of fish on top of each tortilla. Top with the mango slaw. Drizzle on the Sriracha crema and tamarind-plum-garlic sauce. Top with cilantro and pickled serrano chilli. Enjoy!