Using an injector syringe, inject Cajun Injection Marinade into the turkey breast on different angles. If you have any left you can pour it over the top.
Allow to sit at room temperature for an hour, marinating. Reinject as it seeps out over the course of the hour.
Preheat the oven to 350°F.
Sprinkle the Cajun Seasoning all over the outside of the turkey breast and bake in the oven, uncovered, for about 1-½ hours. Until a meat thermometer reads 160°F. (it will reach the required 165° after you take it out of the oven)
Place a foil tent over the top of the turkey breast and allow to sit for 1 hour before slicing.
Notes
You can use Creole Seasoning instead of Cajun Seasoning - it's almost the same thing.If you have skin on your turkey breast, that's great. When you first put it in the oven, have the temperature set at 450° and cook for 15 minutes skin side up. Then after 15 minutes turn the oven down to 350°. Reduce the cooking time to about 1hr 15. This will keep your crisp skin.A meat thermometer will be important, I like the kind that you can leave in the meat while it's in the oven. Like this one. Set it to 160°F - you'll see it go up to 165 after you remove from the oven.