Pat dry the turkey breast with paper towels and set aside.
In a mixing bowl stir together the butter, garlic, thyme, rosemary, sage, lemon zest, 2 teaspoons salt, 1 teaspoon ground black pepper, and paprika.
Using your fingers, carefully pull the skin away from the meat and rub about half of the butter mixture under the turkey skin.
Rub remaining butter mixture on top and all around the turkey breast.
Season the turkey with remaining salt and pepper.
Pour chicken broth in the bottom of your slow cooker.
Add the turkey to the slow cooker, skin side up.
Cover and cook on LOW for 4 to 5 hours, or until internal temperature of the turkey breast registers at 165˚F. Use a Meat Thermometer and start checking for doneness around the 4-hour mark.
Remove turkey from slow cooker and transfer to an oven-safe dish and let stand for 15 minutes.
In the meantime, turn oven to BROIL.
When ready, broil the turkey for about 4 to 5 minutes, or until skin is browned and crispy.
Remove from oven and let stand 15 minutes.
Slice and serve.