Dice the chicken breast into small, bite-sized pieces for even cooking.
In a small bowl, toss the chicken with cumin, chili powder, sea salt, and black pepper until well coated.
Heat the olive oil in a skillet over medium-high heat and sauté the chicken for 6-8 minutes until golden brown and cooked through.
While the chicken is cooking, toss the shredded cabbage with the juice of half the lime and the chopped cilantro to create a quick slaw.
Warm the corn tortillas in a dry pan or directly over a low gas flame for 30 seconds per side until pliable.
Slice the avocado and finely dice the red onion.
Assemble the tacos by dividing the sautéed chicken between the tortillas, then topping with the cabbage slaw, red onion, and avocado.
Serve immediately with the remaining lime cut into wedges for squeezing over the top.