To make the baja fish, clean and dry the fish, then cut into bite-sized pieces. Place the oil and chili sauce in a small bowl. Place flour in a separate bowl. Dip fish in oil and chili sauce mixture, followed by the flour.
Heat 1/2 tablespoon avocado or olive oil over medium-high heat in a skillet. Cook fish, 3-6 minutes, turning once, or until cooked through (Note: this may need to be done in two batches depending on size of skillet). Set cooked fish aside on a paper towel-lined plate. Season with a squeeze of fresh lime juice, sea salt, and pepper.
Combine sauce ingredients in a blender and blend until smooth. Refrigerate until ready to use.
Blend ingredients for the crema in a blender until smooth. Refrigerate until ready to use.
Pulse cabbage in a food processor until a riced slaw is formed. Transfer cabbage to a large serving bowl and add the sauce. Mix well to combine.
Top the cabbage with baja fish, red pepper, and crema topping. Sprinkle with cotija cheese and pepitas. Season with sea salt and pepper to taste. Serve with tortillas.