In a large bowl, pour hot water over margarine. Stir in powdered milk, salt, sugar and egg. Add flour, 1/2 cup at a time, mixing well after each addition. Knead 3 to 4 minutes, adding more flour if necessary to make a very stiff dough. Pat or roll to 1/2 inch thickness and cut out with a dog biscuit cutter. Place on a greased baking sheet and bake at 325 degrees for 50 minutes. Allow to cool and dry out till hard.
I bake these on an ungreased 14 x 15 1/2 inch air bake pan which it *fills* using both large and small cookie cutters. They can be placed side by side since there is no rising. They slide right off onto an opened brown bag and cool and harden in no time. I was advised in DOGHOUSE by a learned fellow that it might not be a bag idea to cut the sugar and salt quantities. Gotta watch their health too! Considering what's in the treats to be bought, these are considerably better for them. Shared by Robin Cole in Fidonet Cooking