How to Make It
Heat 1 tablespoon oil in a large nonstick skillet over medium-high. Add shallots, garlic, and thyme; cook 5 minutes, stirring often, until shallots are caramelized. Add spinach; cook 1 minute, stirring constantly, until wilted. Remove from heat.
Combine goat cheese, chives, parsley, and lemon rind in a small bowl.
Holding knife flat and parallel to cutting board, cut horizontally through the center of pork loin, cutting to, but not through, the other side. Open flat, as you would a book. Starting at the center seam, cut horizontally through each half, cutting to, but not through, the other side. Open flat on either side. Place pork between 2 sheets of plastic wrap; pound to an even 1/2-inch thickness using a meat mallet or small, heavy skillet. Remove plastic wrap.
Season with 1/2 teaspoon salt and 1/2 teaspoon pepper. Spread goat cheese mixture evenly over pork; top with the shallot mixture. Roll up pork jelly-roll fashion. Tie with kitchen twine at 1-inch intervals. Sprinkle with remaining 1 teaspoon salt and remaining 1/2 teaspoon pepper.
Wipe pan clean. Heat remaining 1 tablespoon oil over medium-high. Add pork; cook 3 minutes per side or until browned. Place stuffed pork in a 5-quart slow cooker.
Add apricot preserves, butter, and mustard to pan; reduce heat to medium. Cook 1 minute, stirring constantly, until butter melts. Pour over pork loin in the slow cooker. Cover and cook on LOW 7 to 8 hours, or until a meat thermometer inserted in the thickest portion of pork registers 145°F. I cooked mine in the oven at 350 degrees for about 35 minutes and it was just great.
Place pork on a cutting board; let stand 15 minutes. Skim and discard fat from sauce in the slow cooker. Pour sauce into a saucepan; bring to a boil over medium-high. Cook 5 minutes, until reduced to about 1 cup. Stir in vinegar.
Remove and discard twine. Slice pork into 12 slices; serve with sauce.