1. Preheat your oven to 375 F (190 C). Lightly grease a 9×13-inch baking dish with cooking spray or a little olive oil.

2. In a large skillet, heat the olive oil over medium heat. Add the chopped onion and cook for 3-4 minutes until it softens and becomes translucent. Stir in the minced garlic and cook for another minute until fragrant.

3. Add the cubed chicken breasts to the skillet with the onions and garlic. Cook for 5-7 minutes, stirring occasionally, until the chicken is lightly browned on all sides. It doesn’t need to be cooked through at this stage, as it will finish cooking in the oven.

4. In a large mixing bowl, whisk together the condensed cream of chicken soup, milk, dried thyme, and black pepper until smooth.

5. Add the cooked chicken and onion mixture, along with the cubed potatoes, to the bowl with the soup mixture. Stir everything gently until the chicken and potatoes are evenly coated. Fold in 1 1/2 cups of the shredded cheddar cheese.

6. Pour the entire mixture into your prepared 9×13-inch baking dish, spreading it out evenly. Sprinkle the remaining 1/2 cup of shredded cheddar cheese over the top.

7. Bake for 30-35 minutes, or until the potatoes are tender when pierced with a fork, the chicken is cooked through, and the cheese on top is melted and bubbly with a golden-brown crust.

8. Remove the dish from the oven and let it rest for 5 minutes before serving. Garnish with fresh parsley if desired.