If you love turkey but prefer to eat just the white meat, then grilling a turkey breast is a great option to avoid the mess of preparing a whole bird in the oven. Cooking turkey on a gas grill seals in the juices and creates a crisp, browned skin that's difficult to achieve in the oven without overcooking the breast itself.
Combine olive oil, rosemary, garlic, kosher salt, and ground black pepper in a 2.5 gallon plastic bag. Add the turkey breast, seal the bag, and gently shake the marinade around the meat. Marinate the turkey in the refrigerator for 4 hours, and set it out on the kitchen counter for 1 hour before cooking to bring the meat to room temperature.
Preheat the gas grill to high. Put the turkey breast on the grill with the bone facing down, and lower the grill temperature setting to medium. Insert a cooking thermometer into the thickest part of the breast. Close the grill hood.
After 30 minutes, when the cooking thermometer registers approximately 100 degrees Fahrenheit, add a handful of fruit wood chips to a smoking box and put it in the back section of the grill.
Pour chicken stock into a disposable aluminum pan and place the turkey breast in the pan with the bone still facing down. Keep the cooking thermometer in, and cover the pan with aluminum foil. Turn the grill heat setting down to low in the back, turn the front burner off entirely, and move the aluminum pan to the front of the grill. Close the grill and let the breast finish cooking for approximately 30 more minutes, until the thermometer reads 163 degrees Fahrenheit.
Turn off the grill, transfer the turkey breast to a platter, and wait 5 minutes to let the internal temperature of the turkey finish rising to 165 degrees Fahrenheit.
Remove the thermometer and serve the turkey.