Place the chicken thighs in the bottom of the slow cooker and season both sides with salt and pepper.
In a mixing bowl, stir together the heavy cream, Parmesan cheese, minced garlic, Italian seasoning, sun-dried tomatoes, and chicken broth until combined.
Pour the cream mixture evenly over the chicken thighs.
Cover and cook on low for 5 to 6 hours, until the chicken is tender and cooked through.
Stir the fresh spinach into the sauce and let it sit for 5 minutes until wilted before serving.