Mix together fish spices in a small bowl. Transfer fish to a large bowl and rub spice mixture on both sides. Refrigerate covered for 30 minutes to 2 hours.
Finely chop cabbage and mix together in a medium bowl with 1/4 teaspoon kosher salt and 1/4 cup torn fresh cilantro. Set aside until dinner.
In a medium bowl or container combine yogurt, mayonnaise, lime juice, finely diced jalapeño pepper and spices for your white sauce. Refrigerate until dinner.
Just before dinner heat and lightly oil a grill pan or your barbeque. Grill the fish skin side up for 3-5 minutes and carefully flip and cook for another 5-7 minutes. Fish should flake slightly when pressed in the centre. Transfer to a serving platter and garnish with lime wedges.
Warm tortilla shells in the microwave for a minute before serving.
With a fork you can add bite sized pieces of fish to your taco shells and top with cabbage and white sauce. Serve the Black Bean Salad as a side dish.