Preheat your grill to medium-high heat.

In a small bowl, mix together the olive oil, chili powder, cumin, garlic powder, onion powder, salt, and black pepper. Rub this mixture all over the chicken breasts.

Place the chicken on the grill and cook for about 6-7 minutes on each side, or until the internal temperature reaches 165°F. Remove from the grill and let rest for 5 minutes before slicing.

While the chicken is resting, prepare the mango salsa. In a medium bowl, combine the diced mango, red onion, jalapeño, cilantro, lime juice, and a pinch of salt. Mix well and set aside.

Warm the corn tortillas on the grill for about 30 seconds on each side or until pliable.

Slice the grilled chicken into strips. Assemble the tacos by placing a few strips of chicken on each tortilla and topping with the fresh mango salsa.