heat the 2 tablespoons olive oil in a large skillet over medium-high heat. cook the 1 ½ pounds boneless skinless chicken thighs or breasts for 3-5 minutes on each side until fully cooked.
Remove the chicken and set aside on a plate. Add the 8 ounces sliced mushrooms and 3 minced garlic cloves to the pan and cook for a few minutes until tender. Remove and set aside.
Reduce the heat to medium and add the 1 cup chicken broth, ½ cup heavy cream, 2 ounces softened cream cheese, 1 teaspoon garlic powder, ½ teaspoon salt, and ¼ teaspoon pepper, and whisk until smooth. Whisk in the 1 tablespoon all-purpose flour and continue to cook for 1-2 minutes until it thickens.
Add the mushrooms and garlic to the sauce followed by the chicken and coat everything in the creamy sauce. Heat for a couple of minutes and serve immediately.