Allow the Turkey breast to thaw in the fridge for 12 hours, or until it is at least halfway thawed.
In a medium bowl combine all of the ingredients of the dry rub, then set aside.
In a large stockpot, or other pot that is large enough to hold the turkey breast with at least 1" of extra space on all sides, combine the water, salt, and half of the dry rub mixture. Keep the remaining dry rub in a sealed container and set aside. Heat the water over medium heat until the salt has dissolved.
Remove from the heat and stir in the ice. to bring the water to at least room temperature. If the water is still warm, allow it to chill in the refrigerator.
Remove the giblets from the turkey and discard or set aside if you would like to use them.
Place the turkey breast into the pot with the brine. Make sure that the turkey is fully submerged in the brine adding additional water if needed.
Place the pot with the turkey and brine back into the fridge and allow it to sit for 8-12 hours.
When the turkey is done brining, remove it from the pot and rinse it inside and out with cold water.
Tear 2, 2' pieces of aluminum foil and fold them into fourths lengthwise. Place the in the bottom of the slow cooker with one strip going across the length and one across the width. the ends of the foil should hang over the edge of the slow cooker. This will serve as a sling to make it super easy to remove the turkey from the slow cooker when cooking is complete.
Place the turkey into the slow cooker, on top of the aluminum foil strips.
Place the aromatics inside the turkey. If there isn't enough room you can also place them in the slow cooker next to the turkey.
Using your hands generously coat the outside of the turkey with the remaining dry rub.
Place the lid on your slow cooker and cook for 8 hours on low or until a meat thermometer inserted into the thickest part of the breast reads 165 degrees F.
If you would like to crisp the skin before serving, preheat the oven to 500 degrees. Spray the outside of the turkey with avocado oil or another mild-flavored oil.
Carefully lift the turkey from the crockpot using the aluminum foil strips (careful, they will be hot!) and place it on a baking dish.
Bake in the preheated oven for 15 minutes. Remove from the oven, Discard the aromatics and lightly cover with foil and allow it to rest for at 15 minutes before slicing.
Nutrition information is provided as a courtesy and is only an estimate.