Place roast, onions, and bell peppers in slow cooker.

Season with Italian seasoning and Italian dressing mix and top with beef broth.

Cook on low for 10-12 hours or on high for 4-6 hours, until meat shreds easily with a fork.

Remove meat from juices and shred in a large bowl.

Using a slotted spoon, remove peppers and onions from juices and combine with shredded meat.

Preheat oven to 400 degrees F.

Pile meat and pepper mixture on bun and top with Pepper Jack slices and pepperoncinis or pickled veggies, and top with remaining bun half.

Wrap in foil and bake in preheated oven for 10-12 minutes, until cheese is melty.

Serve and enjoy!