1. Preheat your oven to 400 F (200 C). Wash the sweet potatoes thoroughly, then pierce each one several times with a fork. Place them directly on the oven rack and bake for 35-45 minutes, or until they are very tender when squeezed.

2. While the sweet potatoes are baking, pat the chicken breasts dry with paper towels. Season them generously with salt and pepper. Heat the olive oil in a large skillet over medium-high heat. Add the chicken breasts and cook for 6-8 minutes per side, or until golden brown and cooked through (internal temperature reaches 165 F (74 C)). Remove the chicken from the skillet, let it rest for a few minutes, then shred or dice it into small pieces.

3. In the same skillet, add the chopped onion and cook over medium heat for 3-4 minutes until softened and translucent. Add the minced garlic and cook for another minute until fragrant. Stir in the fresh spinach a handful at a time, allowing it to wilt down before adding more. This will take about 3-5 minutes.

4. Once the spinach has wilted, pour in the chicken broth and bring it to a simmer, scraping up any browned bits from the bottom of the pan. Reduce the heat to low, then stir in the softened cream cheese, Parmesan cheese, and dried thyme until the cheese is melted and the mixture is smooth and creamy.

5. Add the shredded or diced chicken back into the skillet with the spinach mixture. Stir well to combine everything, ensuring the chicken is thoroughly coated in the creamy sauce. Taste and adjust seasoning with salt and pepper as needed.

6. Once the sweet potatoes are tender, carefully remove them from the oven. Slice each sweet potato lengthwise down the middle, being careful not to cut all the way through the bottom. Gently scoop out some of the cooked sweet potato flesh into a bowl, leaving a border of about 1/2 inch of flesh attached to the skin to form a sturdy “boat.” Mash the scooped-out sweet potato flesh lightly with a fork, then stir it into the chicken and spinach mixture.

7. Spoon the chicken and spinach filling generously into each sweet potato shell. You can return them to the oven for an additional 5-10 minutes if you like, just to warm everything through and lightly brown the tops, or serve them immediately. Garnish with fresh chopped parsley if desired.