Slice the chicken breast into thin strips and thinly slice the bell peppers and red onion.
In a small bowl, combine the chili powder, cumin, garlic powder, sea salt, and black pepper.
Toss the chicken strips in the spice mixture until evenly coated.
Heat the olive oil in a large skillet over medium-high heat.
Add the chicken to the skillet and cook for 5-6 minutes until browned and cooked through, then remove from the pan and set aside.
Add the peppers and onions to the same skillet and sauté for 3-4 minutes until they are tender-crisp and slightly charred.
Return the chicken to the skillet and toss with the vegetables to combine.
Warm the corn tortillas in a dry pan or over an open flame for 30 seconds per side.
Divide the chicken and vegetable mixture between the tortillas.
Top each taco with a dollop of Greek yogurt, fresh cilantro, and a squeeze of lime juice.