Heat olive oil in a skillet over medium-high heat. Season pork with salt and pepper then place pork loin in the skillet and sear until browned on all sides (about 2-3 minutes on each side).
Place pork in a slow cooker sprayed with nonstick cooking spray. In a small bowl, whisk together sauce ingredients and pour over pork. Cover and cook on low for 8-10 hours. When done cooking, use two forks to shred pork and mix in with drippings left in the slow cooker.
Preheat oven to 400 degrees F. Line a baking sheet with parchment paper. Cut french bread in half lengthwise and place cut side up on baking sheet.
Spread 2 Tablespoons of mustard on each half of the bread, then top with pickles, shredded pork, ham and shredded cheese.
Cook for 10-12 minutes, or until cheese is melted and golden brown. Cut into slices and serve.