Preheat your oven to 400°F (200°C) and grease a 9x13-inch baking dish.

In a mixing bowl, toss the boneless skinless chicken breast cubes with half of the salt, black pepper, garlic powder, and one-quarter of the onion powder.

Heat a tablespoon of olive oil in a large skillet over medium-high heat. Add the seasoned chicken cubes and sauté for 3-4 minutes.

In the same skillet, add more olive oil if needed, and toss in the cut potato chunks. Sauté for 5-7 minutes.

In a medium saucepan, melt three tablespoons of unsalted butter over medium heat. Stir in three tablespoons of all-purpose flour to form a roux.

Gradually whisk in 2 cups of milk, stirring until the sauce thickens and bubbles, about 5 minutes.

Once thickened, reduce the heat to low, and add the remaining garlic powder, onion powder, shredded mozzarella, and grated Parmesan cheese. Stir until smooth.

In the greased baking dish, combine the pre-seared chicken and sautéed potatoes. Pour the cheese sauce evenly over the top.

Sprinkle the remaining mozzarella cheese over the bake and place it in the preheated oven to bake for 20-25 minutes.

Let it rest for about 5 minutes before serving and garnish with fresh parsley.