Pat the fish fillets dry with a paper towel and season generously with chili powder, salt, and pepper.

Heat oil in a large skillet over medium-high heat. Fry the fish for 3 to 4 minutes per side until crispy and flaky.

In a blender, combine avocado, cilantro, sour cream, and lime juice. Blend until smooth to create the green sauce.

Warm the corn tortillas in a dry skillet until soft and pliable.

Assemble the tacos by layering fish, shredded cabbage, and a drizzle of the avocado cilantro crema on each tortilla.