First things first, preheat your oven. Crank it up to 375°F (190°C). While it's heating, grab a baking dish big enough to hold your peppers comfortably in a single layer.
Now, let's prep those peppers. Wash them well. You have two main options: either cut them in half lengthwise from the stem down (this makes them easier to stuff and eat, in my opinion!) or slice off the tops and scoop out the seeds and membranes. Whichever way you go, make sure all the seeds are out!
Time for the glorious filling! In a medium bowl, combine your shredded cooked chicken, chopped fresh spinach, softened cream cheese, half of the shredded mozzarella cheese (we'll use the rest later!), and the Italian seasoning.
Grab a spoon or spatula and mix everything together really well. You want that cream cheese to get completely incorporated, coating everything in creamy goodness. It might take a little effort, but it's worth it!
Now for the fun part: stuffing the peppers! Spoon the chicken and spinach mixture generously into each pepper half (or whole pepper cavity, depending on how you cut them). Really pack it in there, but don't let it overflow too much before baking.
Carefully place the stuffed peppers into your prepared baking dish. If you cut them in half, they should sit nicely.
Pop the dish into your preheated oven. Bake for about 30-40 minutes, or until the peppers are tender when pierced with a fork. The filling will be heated through, and the cream cheese will be melted and bubbly.
Almost there! Take the dish out of the oven and sprinkle the remaining shredded mozzarella cheese over the top of each stuffed pepper.
Return the dish to the oven for another 5-10 minutes, or until the mozzarella is melted, bubbly, and slightly golden brown. This is where the magic happens!
Carefully remove from the oven (they'll be hot!). Let them cool for just a few minutes before serving. Enjoy your amazing, cheesy, comforting dinner!