For the tortillas: Brush a hot griddle with oil and heat the tortillas on each side to brown them up a bit. Wrap them in foil to keep hot until it's time to eat.
For the fish: In a bowl, combine the chile powder, garlic salt, lime juice and 2 tablespoons of the olive oil. Toss the mixture with the fish in a shallow container and marinate for 15 minutes.
For the chipotle sauce: In the meantime, combine the mayonnaise, cilantro, honey, chipotles, lime juice and salt in a food processor and blend until creamy and smooth. Transfer the sauce to a container (I like to store it in a squeeze bottle) and refrigerate until ready to serve.
Put the remaining 2 tablespoons olive oil in a large skillet over medium heat. Add the fish and cook for 3 to 4 minutes per side. Remove to a plate and flake with a fork.
To build each taco, spoon some fish onto 2 stacked tortillas (see Cook's Note). Top with some chipotle sauce, cabbage, cilantro and Pico de Gallo.
In a medium bowl, combine the tomatoes, onions, jalapenos, cilantro and lime juice. Season with salt and pepper.
Double up on the tortillas to avoid soggy or falling-apart tacos.