Preheat oven to 425 degrees. Line a large baking sheet with parchment paper and lightly grease with cooking spray.
Prepare the cashew crust. Add cashews to a food processor and crush into a breadcrumb-like powder, then transfer to a shallow dish. Add chopped parsley, ground sage, salt and pepper and stir to combine. Set aside.
Prepare the egg wash. Whisk together eggs and water in a shallow dish until combined, then set aside.
Coat the sliced cod in the egg wash, then transfer to the cashew crust and coat well. Lay fish strips flat on the baking sheet, spacing them at least a half-inch apart.
Lightly grease the fish with cooking spray, then bake for 10 minutes or until cashew crust is lightly browned and fish is cooked through.
Next, prepare the lemon herb aioli. Add all ingredients to a small bowl and whisk until well-combined and the consistency is creamy and pourable, but not too thin.* Refrigerate until ready to serve.
Finally, prepare the quick pickled cabbage. Add thinly sliced red cabbage to a large bowl and season with lemon juice and sea salt. Gently toss to combine and let rest for about 10 minutes before serving.
Once all the components are ready, assemble the tacos. Warm the tortillas on a skillet over medium-high heat or in the microwave, then fill each with a few strips of fish, a drizzle of lemon herb aioli, and a handful of cabbage. Optionally garnish with fresh chopped parsley and a lemon wedge. Serve immediately.