As ive said before Len poli has tons of recipes ,
pepperoni is one of the harder things to master, example is what seth just did . no need to cold bath makes casing turn out crap....
Ill tell you how I was taught by my chefs then by the sausage master I trained behind many years ago .
First of make sure you mix you want the mixture is a bit pasty.
Next into smoker on heat till they start to shrivel up and turn color 140 F,(for my smoker about 5 hours) then I smoke for about a hour and half same temp 140 to 155 but this is my smoker as it does a quick and VERY heavy smoke. unlike a lil chief or bradly that for you to decide.
When smoker is done i then transfer into my convection oven at 160 only and door is wedged open about a inch so moisture and a bit of heat can escape bring the product up to temp. 158 to kill any pathogans, then after its all done lay on top of cooling racks this method will give the casing a nice "crunch" just like garage station quality LOL
pics below are on heat then smoke then finished product remeber low and slow if you turn up hotter and try and rush it sometimes you render the fat and now its dog food