Preheat broiler to high. In a small bowl, whisk together spices with olive oil. Spread all over tilapia filets and broil in small baking dish for 5-7 minutes or until internal temperature reaches 145 degrees F.
Warm the tortillas in the microwave or oven for a few seconds.
Make the crema sauce by whisking together yogurt, hot sauce and salt until smooth.
Make pickled onions by very thinly slicing a red onion and placing into a small mason jar. Whisk ½ cup apple cider vinegar, 1 tablespoon sugar and 1 cup water until solids are dissolved. Then pour over onion in jar. Close and refrigerate for at least one hour or overnight. Can be made ahead of time and will stay good in fridge for one week.
Divide cabbage over warm tortillas, then top with fish and drizzle with crema sauce. Add pickled onions, jalapeños, cilantro or other toppings as desired.