Start by patting the fish dry with paper towels and seasoning it with ¼ tsp of salt. Place the fish in a small baking dish or a wide bowl.

In a separate small bowl, mix together 2 Tbsp of olive oil, orange juice, and taco seasoning. Whisk until well combined, then pour this mixture over the fish, turning it gently to ensure it's evenly coated. Cover and refrigerate for at least 30 minutes, or up to 2 hours.

For the mango salsa, combine the diced mango, red bell pepper, red onion, cilantro, minced jalapeño, lime juice, cumin, and salt in a large bowl. Stir well to mix everything together and refrigerate until you're ready to use it.

To make the Baja sauce and slaw, whisk together the Greek yogurt (or sour cream), mayonnaise, lime juice, Old Bay Seasoning, and a dash of hot sauce in a small bowl. In a large bowl, add the shredded cabbage and season it with a pinch of salt. Mix in 3 Tbsp of the Baja sauce, reserving the rest for topping later. Toss the slaw to combine and set it aside.

Heat the remaining 2 Tbsp of olive oil in a large skillet over medium-high heat. Once hot, add the marinated fish and cook it undisturbed for about 4 minutes. Carefully flip the fish and cook for another 3 to 4 minutes, until it feels firm to the touch. Transfer the fish to a plate and flake it into large chunks.

To assemble the tacos, place a small amount of slaw in each warmed tortilla, followed by the flaked fish, mango salsa, and a drizzle of the remaining Baja sauce.

If you want to prepare ahead, the mango salsa can be made up to 1 day in advance and stored in an airtight container in the refrigerator. For best freshness, store all components separately. The fish can be kept refrigerated for up to 2 days, but the slaw is best used within 1 day. It's recommended to only make the amount of slaw you plan to use immediately and save the rest.

To reheat the fish, drizzle a little olive oil in a skillet over medium heat. Once hot, add the fish and gently warm it for 3 to 4 minutes.