Spray the crockpot with nonstick cooking spray or use a liner for easy cleanup.

Place the sliced onions at the bottom of the crockpot and pour in ½ cup of beef broth.

Prepare the pork: Trim any silver skin or excess fat from the pork loin, then place it on top of the onions. Sprinkle the seasonings evenly over the pork, including the garlic. Spread the mustard over the top in an even layer.

Drizzle the apple cider vinegar, honey, and maple syrup over the pork.

Cover and cook on low for 7–8 hours, or until the pork reaches an internal temperature of at least 145°F.

Remove the pork from the crockpot, transfer it to a plate, and shred it using two forks.

Make the gravy: Strain the remaining liquid from the crockpot into a saucepan. Add the remaining 1 cup of beef broth and bring to a boil. Reduce to a simmer. In a small bowl, mix cornstarch with cold water until smooth, then whisk it into the sauce. Stir until the gravy thickens.

Serve: Pour the gravy over the shredded pork or serve it on the side