Heat olive oil in a skillet over medium heat.
Sear the beef chuck roast on all sides until browned.
Remove the roast and place it in a slow cooker.
In the same skillet, sauté the sliced onion until softened.
Add garlic and cook for an additional minute.
Pour in beef broth and stir in Italian seasoning and red pepper flakes.
Bring the mixture to a simmer, then pour over the beef in the slow cooker.
Cover and cook on low for 6 hours, or until the beef is fork-tender.
Once cooked, shred the beef and mix it with the gravy.
Serve on Italian rolls with giardiniera and provolone cheese if desired.