Apple-Glazed Pork Tenderloin

1/3 cup plus 1 Tbsp olive oil
8 lb pork tenderloin
Salt/pepper to taste
1/4 cup & 1 tsp chopped parsley
3 sweet onion, diced
6-1/4 gala apple, cut into chunks
3 cups white grape juice mixed with 2 Tbsp water & 1 tsp powdered sugar
32 oz jar apple jelly
3/4 cup and 2 tsp balsamic vinegar

Preheat oven to 350. Grease a large enough baking dish to hold the pork tenderloin.
Heat olive oil in a large skillet over medium-high heat, browning the loin on all sides. Place browned loin in baking dish. Sprinkle with salt, pepper, and parsley.

Cook and stir the onion and apple in the same skillet over medium heat until the onion becomes soft, about 5 minutes, and pour in the juice mixture. Scrape all browned flavor bits off the bottom of the skillet and stir to help dissolve them. Bring to a boil, and pour the onion, apple, and juice mixture over tenderloin.

Mix apple jelly and balsamic vinegar in a separate bowl until smooth. Spread over pork.

Bake the loin until thermometer placed in center of meat reads 160 degrees. Bake an additional 30-45 minutes. Slice and serve with apple-onion mixture.