Step 1

Make the slaw: Place the cabbage in a colander or strainer and sprinkle with the salt. Massage and squeeze the cabbage with your hands to help it release its liquid and begin wilting. Place in the sink or over another bowl, and set aside to drain for about 15 minutes.

Step 2

Using your hands, squeeze the cabbage of its excess liquid one handful at a time, and transfer to a large bowl. Add the carrot, scallions, and jalapeño if using. Toss to combine. Add the mayonnaise, lime juice, and garlic and toss to combine. Taste and season with a sweetener, salt, or pepper as needed.

Step 3

Make the fish: Combine the flour, salt, pepper, and paprika in a shallow container. Pat the fish dry with paper towels, then dredge it in the flour mixture until evenly coated.

Step 4

Heat the oil in a heavy (preferably cast iron) pan over medium-high heat until shimmering. Add the fish in a single layer, working in batches if needed. Cook undisturbed until golden-brown on the bottom, 2 to 3 minutes. Using a flat spatula, carefully flip the fish, but don't worry if it falls apart a bit. Continue cooking until the second side is golden brown and the fish is opaque and flakes apart easily in the thickest part, 2 to 3 minutes more. Transfer the fish to a clean plate and flake into large chunks; keep warm.

Step 5

Heat the corn tortillas, one by one, in a heavy, dry pan, until soft and warm. Wrap them in a clean kitchen towel as you go. (Alternatively, wrap them in a clean kitchen towel and warm them in the microwave for a few seconds.)

Step 6

Serve the fish with the tortillas, slaw, cilantro, avocado, lime, and salsa on the side, letting each diner assemble his or her own tacos. These tacos are made and eaten immediately.