Preheat oven to 375℉.
Place biscuits on a baking sheet and par-bake biscuits for 8 minutes.
Remove biscuits from oven and set aside. Leave oven on.
While the biscuits are baking, spray a 13X9 inch oven safe casserole dish. Set aside.
Melt half the butter in a pot over medium heat.
Add frozen vegetables to the pot and stir with the butter. Cook for 5 minutes or until heated through.
Add the cream of chicken soup, milk, shredded chicken meat, salt, pepper, and garlic powder to the pot.
Stir to combine.
Heat mixture for 10 minutes or until the filling mixture is hot and bubbly and completely heated through.
Transfer filling into the prepared casserole dish.
Place par-baked biscuits, baked side down and raw side up, on top of the filling in the casserole dish.
Melt remaining 2 tablespoons butter. Baste the tops of the biscuits with the melted butter.
Bake for 10 minutes, tent casserole with a piece of foil and bake for an additional 10-12 minutes.
To serve: Spoon filling over a bed of mashed potatoes, top each serving with a biscuit and garnish with a sprinkle of freshly chopped chives.