Preheat the oven to 400 degrees.
In a small bowl, mix the lemon, rosemary, thyme, marjoram and minced garlic.
Heat the oil in a large cast-iron skillet over medium-high heat. Season the chicken breasts with salt and pepper and then place in skillet, along with the sweet potato cubes and onion slices. Cook until the chicken breast is brown, about 5 minutes.
Flip chicken over, stir in the goji berries and pour the lemon mixture over the skillet contents. Top with the lemon slices and bake for 30 minutes, or until the chicken is cooked through. Serve and enjoy!