Creamy Garlic Chicken Spanakopita Skillet Recipe

Name: Creamy Garlic Chicken Spanakopita Skillet Recipe
Ingredients: 1 pound fresh baby spinach leaves, washed; 6 tablespoons unsalted butter, divided; 1 1/2 pounds boneless, skinless chicken breasts or thighs, chopped into 1-inch chunks; Kosher salt and freshly ground black pepper; 5 medium cloves garlic, minced; 2 tablespoons all-purpose flour; 1/2 cup homemade chicken stock or low-sodium broth, plus more as needed; 1/2 cup half and half; 6 ounces feta cheese, crumbled; 3 scallions, white and light green parts only, chopped; 1 small bunch dill, chopped, plus more for garnish; 6 to 8 sheets phyllo dough, thawed and covered with a towel