Fill up your meat injector with the Sriracha beer marinade. Inject the turkey all over. I usually inject each breast, each leg, each wing, each thigh, and both sides of the back of the turkey.
Pat dry with paper towels. This is important if you want crispy skin. (And what kind of a psycho doesn't want crispy skin??)
Sprinkle with the cajun spice rub. Massage into the skin.
Brush all over with oil.
Fill cavity with the bell peppers, celery, and onion. Place additional veggies around the turkey in the roasting pan.
Cook 2-3 hours, basting occasionally. Turkey is done when the thickest part of the breast is 165°.
Remove from oven and let rest for 20 minutes until carving.