Preheat oven to 350 degrees. Spray a "9 x 13" baking dish with non-stick cooking spray.
In prepared baking dish place cooked chicken, cream of chicken soup, sour cream, cheddar cheese, frozen vegetables, minced garlic, salt, pepper, onion powder, and garlic power. Mix well and evenly distribute mixture.
Remove biscuits out of tube. Pull each biscuit into 2 halves. Cut each half into halves. Cut each of the halves into 3 pieces. Push each piece of biscuit into the pot pie mixture leaving just a little room between each piece of biscuit so you can see the mixture. (NOTE: Do not cut all of the biscuits as the whole can won't fit. So I usually place the 3-4 whole biscuits left over onto another lightly sprayed cookie sheet to cook along side of the casserole.)
Brush the melted butter onto each biscuit piece in the casserole dish.
Cover baking dish with foil and place in oven. Bake for 20 minutes covered. Remove foil and bake another 20 -25 minutes uncovered until biscuits are fully cooked and golden brown on top and on bottom. Pot Pie Casserole should also be heated through and bubbly.
Let sit for 5-7 minutes before serving. Enjoy.