Preheat oven to 425ºF. Line a rimmed baking sheet with foil and grease it with a bit of avocado oil to prevent the fish from sticking. Set aside.
Combine the salt, coriander, paprika, and cumin in a small bowl. Season fish with the seasoning and place onto the prepared baking sheet.
Combine the butter and garlic and melt together (either in a microwave-safe bowl in the microwave for a few seconds or on the stovetop in a small pan over medium heat). Add the lemon juice and zest. Pour over fish on the baking sheet.
Bake for 10-12 minutes, or until the fish just flakes when tested with a fork. Sprinkle with parsley and serve.