Preheat your oven to 375°F. Spray a 9x13 baking dish with nonstick cooking spray and set it aside.

Add the cream of mushroom soup, butter, and all of the seasonings including the seasoned salt, garlic powder, onion powder, and black pepper, into a large bowl.

Use a whisk to mix everything together until it is fully incorporated and semi-smooth. Add your frozen mixed vegetables into the soup mixture and use a spoon to stir them together until combined. 

Pour the creamy vegetable mixture into the baking dish and cover it with aluminum foil. Place the dish in the oven and bake for 20 minutes. 

Remove the foil from the dish and bake for an additional 10-20 minutes, depending on how tender or tender-crispy you like your vegetables. 

Once they are to your liking, remove them from the oven and serve immediately.