In a large mixing bowl, combine the shredded chicken, frozen peas and carrots, diced potatoes, onion, minced garlic, cream of chicken soup, chicken broth, thyme, black pepper, and salt. Mix until well combined.
Pour the chicken mixture into a greased 9x13 inch casserole dish, spreading it evenly across the bottom.
Sprinkle the shredded cheddar cheese over the chicken mixture.
Take the biscuit dough and cut each biscuit into quarters. Scatter the biscuit pieces evenly over the top of the casserole.
Bake in the preheated oven for 25-30 minutes, or until the biscuits are golden brown and the filling is bubbling.
Remove the casserole from the oven and let it cool for 5-10 minutes before serving.
Notes
Serve the casserole hot directly from the dish, garnished with fresh parsley for a pop of color.