White Steak Gravy

My family loves cube steak fried with a white gravy over it and this recipe is the best I've found. It's very easy, thick and delicious!

2 cups water
2/3 cups dry milk powder
1/3-cup flour
1/2 tsp.  salt
1/4 tsp.   pepper
1/2 tsp. seasoning salt

In the order given, put all ingredients into blender. Blend briefly on high till smooth. Pour into a saucepan.
Using a wire whisk, stir constantly while cooking on medium-heat till comes to a boil and begins to thicken.  Turn down to lowest setting and stir frequently until ready to use.