Prepare the turkey breast by patting it dry with paper towels. This helps achieve a nice crust.
In a small bowl, mix together the salt, black pepper, garlic powder, onion powder, thyme, and rosemary to create a seasoning blend.
Rub the olive oil over the turkey breast, then generously coat it with the seasoning mix, ensuring it covers all sides.
Place the chopped onion and minced garlic at the bottom of the slow cooker. This will create a flavorful base for the turkey.
Pour the chicken broth over the onions and garlic in the slow cooker.
Carefully place the seasoned turkey breast on top of the onion and garlic mixture.
Cover the slow cooker with its lid and cook on low for about 6 hours, or until the turkey reaches an internal temperature of 165°F (75°C).
Once the turkey is fully cooked, remove it from the slow cooker and let it rest for about 15-20 minutes before slicing. This ensures the juices redistribute for a more tender turkey.
Serve with your choice of sides and garnish with fresh herbs if desired.