In a food processor or blender, add the crackers, flaxseed and spices. Pulse until it reaches a flour-like consistency. *If you don't have a food processor, feel free to use a large ziplock bag, throw all ingredients inside, zip it up and use the bottom of a glass or flat surface to pound it down until it reaches a flour-like consistency.
Pour mixture in a deep dish bowl. In a separate deep dish bowl, whisk one egg.
Prepare your assembly line: bowl with egg, breading mixture, clean plate.
Rinse cod then pat dry with paper towel and lay flat on a plate. Using tongs or a fork, dip the fish in the egg wash, making sure to cover the entire fillet, then let the excess egg drip off before transferring to the breading mixture. Cover the cod completely in the mixture, making sure to pat down with the tongs so that the mix sticks, then transfer to a clean plate.
Heat a large skillet with avocado oil on medium. Transfer the cod to the skillet and let cook until golden brown on each side, about 4-6 min. Be gentle when flipping so that the mixture doesn't fall off. You can turn down the heat and cover to allow center to fully cook. Fish should be fork tender. Once completely golden brown, transfer to a clean plate to cool for 2-3 minutes before serving.
Heat your tortillas over an open flame until it chars on either side, or heat in a skillet.
Build your tacos! :)