Creating Tuscan Slow Cooker Chicken Stew is straightforward and requires just a few simple steps:

1. Prepare the Ingredients: Dice the onion, mince the garlic, and chop the vegetables as noted in the ingredient list.
2. Brown the Chicken: In a skillet, heat the olive oil over medium heat. Add the chicken thighs, season with salt and pepper, and brown on both sides for about 3-4 minutes. This step adds flavor but can be skipped if you’re short on time.
3. Transfer to Slow Cooker: Place the browned chicken in the slow cooker.
4. Add Vegetables: Layer the diced onion, garlic, carrots, celery, and red bell pepper over the chicken.
5. Incorporate Tomatoes and Broth: Pour in the diced tomatoes and chicken broth. Stir gently to combine.
6. Season: Sprinkle oregano, thyme, and rosemary over the top. Adjust salt and pepper according to your taste.
7. Cook: Cover the slow cooker and set it to low for 6-8 hours or high for 4-6 hours.
8. Add Spinach: About 30 minutes before serving, stir in the fresh spinach. Cover and continue to cook until wilted.
9. Shred Chicken: Once cooked, shred the chicken in the slow cooker with two forks, mixing it back into the stew.
10. Serve: Ladle the stew into bowls and garnish with fresh parsley, if desired.

These steps will guide you effortlessly in preparing this incredible Tuscan dish.