Begin by trimming excess fat from the pork loin, if needed. Pat it dry with paper towels and season with salt, black pepper, thyme, rosemary, and red pepper flakes.
In a mixing bowl, combine the balsamic vinegar, honey, soy sauce, and minced garlic. Whisk until well blended.
Place the seasoned pork loin in the slow cooker. Pour the balsamic mixture over the pork, ensuring it is well coated.
Cover the slow cooker and set it to low for 8 hours. Allow the pork to cook undisturbed.
Once the cooking time is complete, use tongs or a fork to carefully remove the pork loin from the slow cooker and place it on a cutting board. Let it rest for 10 minutes.
While the pork rests, you can optionally turn the slow cooker to high and let the sauce thicken for an additional 15-30 minutes.
Slice or shred the pork loin, then drizzle some of the sauce from the slow cooker over the top. Garnish with fresh parsley before serving.