Preheat grill or grill pan to medium-high.
Combine all spices in a small bowl. Drizzle chicken breasts with oil and rub them generously with spice mixture, reserving a handful for the peppers.
Grill chicken until cooked through.
Brush pepper slices with oil, sprinkle with seasoning, and grill until tender.
Brush corn tortillas (2 per taco) with light butter and grill until warm.
Slice chicken and assemble tacos by filling tortillas with some of each type pepper, chicken, lettuce and tomato.
Serve with lime wedges and Bush's Black bean Fiesta alongside