Season the chicken breasts with the kosher salt and black pepper.

Combine the margarita mix, lime and orange juices, tequila, triple sec and honey in a blender.

Add the cilantro, coarsely ground black pepper, garlic and onion powder. Process on high speed until the mixture is smooth, then reduce the speed and add the olive oil.

Put the seasoned chicken breasts in a baking dish or container. Pour the blended mixture over the chicken, turning it once so that both sides are coated.

Cover the dish and refrigerate for at least 6 hours - overnight is best.

Light a charcoal barbeque or heat a gas grill for medium high heat. Lightly oil the grate.

Shake any excess marinade off the chicken breasts and discard the marinade.

Grill them for about 7 minutes per side. The internal temperature of the breasts should reach 180F.