Substitute milk for the liquid in the dough. You may need to add just a touch more to get the dough to the correct consistency, but you should be fine doing that.
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What is equivalent to 3/4 cup of powdered milk if I don't have any?
Alyssa
RE: Substitute For Powdered Milk
Does the recipe call for the powdered milk to be "dry" or reconstituted? I have a recipe which calls for the powdered milk be used "dry". If that is the case you might try dry coffee creamer.