Start by rolling out your pizza dough on a lightly floured surface. Shape it into an 8-inch circle or a 12-inch base, depending on your preference. Transfer the dough to a parchment-lined baking sheet or pizza stone for easy handling.
In a large skillet, melt the butter over medium heat. Add the flour and whisk until it forms a smooth paste (your roux). Gradually pour in the milk, whisking constantly to avoid lumps. Cook for 2-3 minutes until the sauce thickens. Season with nutmeg, salt, and pepper, then remove from heat.
Spread the creamy sauce evenly over the prepared dough, leaving a small border around the edges. Layer the shredded chicken, peas, and carrots evenly across the surface. Top it all off with mozzarella and Parmesan cheese for that gooey, cheesy finish.
Preheat your oven to 450°F. Bake the pizza for 12-15 minutes, or until the crust is golden and the cheese is bubbling.
Once out of the oven, sprinkle fresh parsley over the top for a burst of color. Slice it up and serve hot for the ultimate comfort food experience!