Combine chicken, vegetables, soups, and milk in a greased baking dish. Taste and season with salt and pepper as desired.
Place biscuits over the top of the casserole. Brush with melted garlic butter (optional).
Bake uncovered for 10 minutes, cover with foil and bake an additional 30-35 minutes or until biscuits are cooked through and casserole is bubbly.
Notes
Keep leftover chicken pot pie casserole in an airtight container in the refrigerator for up to 4 days. Freeze leftover filling and biscuits separately in zippered bags for up to one month. Thaw in the refrigerator before reheating.