Begin by patting the fish fillets dry with paper towels. In a bowl, combine flour, cornmeal, paprika, garlic powder, salt, and black pepper, then coat each fillet in this mixture. Dip them into a mixture of beaten egg and buttermilk, and then coat them again in the flour mixture to create a double crunch.

Heat about 1 inch of vegetable oil in a large skillet over medium-high heat until shimmering. Carefully place the coated fish fillets in the hot oil, frying for approximately 3-4 minutes on each side until golden brown and crispy. Remove from skillet and drain on paper towels.

In a large mixing bowl, combine shredded cabbage, grated carrots, chopped fresh cilantro, lime juice, olive oil, salt, and black pepper. Toss everything together until well-coated, allowing the flavors to meld.

In a separate bowl, mix mayonnaise, sour cream, lime juice, garlic powder, and optional hot sauce until smooth. Adjust seasoning as necessary.

Warm tortillas in a dry skillet over medium heat for about 30 seconds on each side. Layer each tortilla with a piece of fried fish, add slaw, and drizzle with creamy sauce. Add optional toppings like salsa.

Serve the assembled Baja Fish Tacos immediately while the fish is still crispy.