In a large pot, heat butter over medium heat. Add onions and sauté until soft and translucent. Season with salt, pepper, garlic powder, paprika, and poultry seasoning.
Stir in flour until combined. Slowly add water and milk, about a half cup at a time, and whisk until combined.
Add potatoes and chicken and stir. Bring to a boil and allow to cook for 10-12 minutes or until potatoes are fork tender.
Stir in frozen veggies, bring to a bowl, reduce heat and continue cooking for 5 minutes or until veggies are heated through. Serve and enjoy!