Roast Pork Loin with Apples

INGREDIENTS

• 3 cloves garlic, smashed
• 2 carrots, thickly sliced
• Kosher salt and freshly ground black pepper
• 2 tablespoons vegetable oil
• 2 stalks celery, thickly, sliced
• 3 sprigs fresh thyme
• 2 tablespoons whole grain mustard
• 2 apples, such as Cortland or Rome peeled, cored and cut into 8 slices
• 2 tablespoons apple cider vinegar
• 3 sprigs fresh rosemary
• 1 cup apple cider
• 4 tablespoons cold unsalted butter
• 1 (2-pound) boneless center cut pork loin, trimmed and tied
• 1 medium onion, thickly sliced