Preheat your oven to 400°F.
In a small bowl, whisk together honey, Dijon mustard, apple cider vinegar, minced garlic, salt, and pepper to create the glaze.
Place the pork tenderloin on a baking tray and brush generously with the glaze, ensuring all sides are coated.
Roast the pork in the preheated oven for about 20-25 minutes or until it reaches an internal temperature of 145°F. Turn the tenderloin once halfway through for even cooking.
While the pork roasts, trim the Brussels sprouts and halve them. Toss them in olive oil, salt, and pepper, then spread on a separate baking sheet.
Roast the Brussels sprouts in the oven for about 15-20 minutes, stirring once, until they are tender and slightly crispy on the edges.
Once the pork is done, let it rest for 5 minutes before slicing. Serve with a side of roasted Brussels sprouts and drizzle any remaining glaze over the pork if desired.