Combine sour cream, avocado, cilantro, 1 tbsp lime juice, lime zest, jalapeno and serrano pepper in a blender; process until smooth. Transfer to a small bowl and refrigerate.

Combine paprika, brown sugar, garlic powder, onion powder, salt, cumin and chili pepper in a small bowl. Sprinkle seasoning evenly over both sides of the fish filets.

Heat oil in a large cast-iron skillet or sauté pan over medium-high heat. Add fish to pan; cook 2-3 minutes on each side or until desired degree of doneness.

Combine tomatoes, red and green cabbage and cilantro in a bowl. Cut a wedge of lime and lightly sqeeze over slaw. Toss slaw adding salt and pepper to taste. Warm tortillas according to package directions. Divide fish evenly among tortillas and cover with the slaw.