In a large bowl, cream together the butter, peanut butter, brown sugar and white sugar until smooth. Beat in the eggs one at a time. Stir in the vanilla and water. Combine the flour, protein powder, bicarb soda and salt; stir into the creamed mixture. Fold in chocolate chips. Drop dough by heaping spoonfuls onto un-greased baking trays.
Bake for 10 to 12 minutes in the preheated oven. Allow biscuits to cool on baking tray for 5 minutes before removing to a wire rack to cool completely.