Dice the chicken breast into small, bite-sized pieces and season with sea salt, black pepper, and garlic powder.
Finely chop the red onion and bell pepper.
Heat the olive oil in a non-stick skillet over medium-high heat.
Add the onion and bell pepper to the skillet, sautéing for 3-4 minutes until softened and slightly caramelized.
Add the chicken to the pan and cook for 5-6 minutes until browned and cooked through.
Stir in the black beans and the chipotle peppers in adobo sauce, allowing the mixture to simmer for 2 minutes to meld the flavors.
While the filling simmers, warm the corn tortillas in a separate dry pan or over an open flame for 30 seconds per side.
Divide the chicken and bean mixture evenly between the two tortillas.
Top each taco with a slice of avocado, a dollop of Greek yogurt, fresh cilantro, and a squeeze of lime juice before serving.