Place roast in a large slow cooker. Add Italian dressing mix, beef broth, pepperoncini, giardiniera, and beer. Cover, and cook on high for 1 hour. Reduce temperature to low, and cook until meat can be shredded between two forks, about 6 to 7 hours more.
Remove roast, and place into a large bowl. Strain cooking liquid and reserve. Shred roast using two forks, removing any excess fat.
Preheat oven to 350°. Place deli rolls on a baking sheet. Add shredded beef onto rolls, and top with cheese. Bake until cheese is melted. Serve with reserved cooking liquid to drizzle on sandwich.
Notes
*Darryl uses Good Seasons.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/darryl-postelnicks-chicago-style-italian-beef/