Heat a skillet over medium-high heat. Once hot, add the olive oil, diced shallot, and minced garlic. Sauté for 1-2 minutes until the shallot starts to become translucent and the garlic is fragrant.
Add the chopped spinach, and sauté for about 2-4 minutes until the spinach are cooked and wilted. Remove from the heat and set aside.
Add the spinach mixture, shredded chicken, softened cream cheese, sour cream, mayo, Calabrian peppers, sundried tomatoes, lemon juice, black pepper, salt, black pepper, chopped artichoke hearts, parmesan cheese, and 1 cup shredded mozzarella cheese to a large mixing bowl. Stir until everything is well combined in a creamy mixture. Taste and add salt as needed.
Preheat the oven to 350 degrees. Transfer the dip to a 10 inch cast-iron skillet and spread in an even layer. Top with remaining 1/2 cup shredded mozzarella cheese. Bake at 350 degrees for 20-25 minutes or until the dip is bubbly. Broil for 1-2 minutes or until the top is golden.
Serve with crostini and veggies and enjoy.