Dice the chicken breast into small, bite-sized pieces.
In a small bowl, toss the chicken with chili powder, cumin, sea salt, and black pepper until evenly coated.
Heat the olive oil in a non-stick skillet over medium-high heat.
Add the chicken to the skillet and sauté for 6-8 minutes, or until cooked through and slightly browned.
While the chicken cooks, mash the avocado in a small bowl and whisk in the Greek yogurt and lime juice until smooth and velvety.
Warm the corn tortillas in a dry pan or over an open flame for 30 seconds per side until pliable.
Divide the cooked chicken between the warm tortillas.
Top each taco with shredded cabbage, a generous dollop of the avocado crema, and fresh cilantro.