Begin by cutting fresh fish fillets into 1-inch strips, ensuring uniform size for even cooking. In a shallow dish, mix all-purpose flour with paprika, garlic powder, cumin, salt, and pepper. Coat each fish strip with the seasoned flour mixture, shaking off any excess.

In a large skillet, pour in about 1 inch of vegetable oil and heat over medium-high. Drop a small piece of fish into the oil to check; it should sizzle immediately.

Carefully add the coated fish strips in batches to the hot oil. Fry for about 3-4 minutes on one side, flipping when golden brown. Cook until all sides are crisp, then transfer to paper towels.

While the fish cools, whisk together sour cream, mayonnaise, lime juice, and zest in a bowl. Add a pinch of salt and adjust lime juice to taste.

In a large bowl, combine shredded green and red cabbage with grated carrot. Squeeze fresh lime juice over and toss well to combine.

Warm corn tortillas in a skillet or microwave. Layer each with crispy fish, slaw, and lime crema. Garnish with fresh cilantro if desired.