In a large bowl, mix together the beef, pork, Prague Powder, salt, garlic powder, black pepper, cayenne pepper, red pepper flakes, and cold water. Make sure everything is well combined.
Place the mixture in the fridge for an hour to chill.
Soak the casings in warm water for 30-60 minutes.
Stuff the meat mixture into the casings using a sausage stuffer. Twist the casing into pepperoni-sized links.
Hang the pepperoni links in the smoker or grill and smoke for 30-35 minutes without smoke, then for 45-60 minutes with smoke.
Use a meat thermometer to ensure the internal temperature of the pepperoni reaches 160°F.
Once the pepperoni is fully cooked, remove it from the smoker and allow it to cool for 10-15 minutes in a cold water bath.
Slice the pepperoni to your desired thickness and enjoy!
Notes
Make sure to use high-quality meat and spices for the best flavor.
Keep the meat mixture cold to prevent the fat from melting and to help the meat stick together better.
Monitor the humidity level during the smoking process to ensure the pepperoni stays moist but doesn't become too wet.
Store the pepperoni in an airtight container in the fridge or freezer until you're ready to use it.