Season the chuck roast on all sides with salt, pepper, and garlic.
Melt butter in a skillet over medium-high heat and sear chuck roast on all sides.
Put the seared chuck roast in a crockpot.
Add sliced onions, minced garlic, Worcestershire sauce, beer, beef broth, and Au Jus packet to the hot skillet stirring and letting it simmer.
Pour the onion and gravy mixture over chuck roast in the crock pot and let cook on low for about 8 hours. Shred the meat and discard any extra fat.
Next, toast the bread. I like to place the bread on a sheet pan in the oven at 400 degrees F for a few minutues.
Build sandwiches on toasted sub rolls with the meat and provolone cheese. Put them back in the oven for just a few minutes to melt the cheese.
Enjoy!