Dice the chicken breast into small, bite-sized pieces and place them in a medium mixing bowl.
Add the chipotle peppers in adobo, lime juice, sea salt, black pepper, and ground cumin to the bowl, tossing until the chicken is thoroughly coated.
In a large skillet, heat the avocado oil over medium-high heat until shimmering.
Add the marinated chicken to the skillet in a single layer and cook for 5-7 minutes, stirring occasionally, until the edges are charred and the chicken is cooked through.
While the chicken cooks, thinly shred the red cabbage and finely dice the red onion.
Warm the corn tortillas in a dry pan or over an open flame for 30 seconds per side until pliable.
Assemble the tacos by dividing the charred chicken between the tortillas, topping with the cabbage slaw, onion, fresh cilantro, and slices of creamy avocado.