Preheat oven to 400 F.
In a small bowl, stir together breadcrumbs, cumin, coriander, and chili powder. Set aside.
Arrange fish on a greased baking tray, or line with foil. Squeeze lime juice (reserve 2 tsp for the fish taco sacuce) over fish and sprinkle with salt and pepper.
Spoon breadcrumb mixture over fish. Bake for 8-10 minutes or until fish flakes easily.
Meanwhile, prepare the fish taco sauce: 1 cup plain greek yogurt, 1/8-1/4 tsp cayenne pepper, 1/2 tsp cumin, 1/2 tsp garlic powder, 2 tsp lime juice.
Arrange tortillas on plate, top with fish, cilantro, orange slices, green chile, and avocado. Spoon fish sauce over each taco. Garnish with lime wedge and cilantro if desired.