I'm wanting to make a peanut butter pie using vanilla cook and serve pudding. Can I do this and would I need to use less liquid?
Welcome! Per allrecipes , yes you can, and no change liquid is needed. The recipe in the link calls for a pre-made graham cracker crust and uses 1 cup of peanut butter.
The instructions read as:
Prepare cook and serve pudding as directed on package. Stir in peanut butter. Bring mixture to a boil and pour into graham cracker crust. Allow to cool.
If you do a Google search, there are also many recipes available that use instant pudding.