Combine the ingredients for the cabbage slaw up to an hour ahead of time and set aside to let the cabbage soften. Stir occasionally.
Combine the ingredients for the chipotle-lime sauce. Taste, adjust spice level, and set aside.
Preheat the oven to 350°.
Cover a baking rack with foil. Cut the fish fillets into half-inch slices and arrange on the foil. Sprinkle with cajun seasoning to taste.
Bake the fish for 12-14 minutes, until fully cooked through and flaky.
While the fish is cooking, heat a nonstick skillet over medium-high heat. Once the pan is hot, spray with cooking spray and set a tortilla in the center. Cook for about 30 seconds on each side, until golden brown spots appear and the edges begin to crisp. Repeat with remaining tortillas.
Serve the cabbage slaw, chipotle-lime sauce, fish, and tortillas separately and assemble your own tacos.