Preheat the oven to 350ยบ. Slice mushrooms and shallots. Chop artichokes and garlic.
Heat about 2 Tbsp ghee or butter in a large, oven-safe skillet. Saute the fillings for about 3-5 minutes, adding the spinach for the last minute.
Meanwhile, carefully cut slits into each breast. Once the filling mixture is cooked through, stuff 1/4 of the mixture into each breast.
Season the top of each breast with salt and pepper. Add another tablespoon of ghee to the same pan, and carefully place each breast into the pan, seasoned side down. Add more salt and pepper to the bare side that is now facing up.
Allow to cook on medium heat for about 5 minutes, then slowly flip over each breast (it's ok if some filling falls out). Brown that side for another 5 minutes, then place in the oven. Cook for an additional 10-12 minutes, until chicken is cooked through!
