Preheat the oven to 350°F
While the oven is preheating, pour the olive oil in the Dutch oven and heat to a medium-high heat.
As the oil is heating pat the pork loin dry and season both sides with salt, pepper, and dried parsley.
Brown the pork loin on all sides.
Then add the sliced onions and garlic for a few minutes until the onions are tender and slightly brown.
Next add in the beef broth, heat to a boil, remove from the heat and cover.
Place the Dutch oven in the oven for 30 minutes at 350°F
Flip the pork loin and bake for another 30 minutes.
Remove the Dutch oven and place it back on the stovetop. Place the pork loin on a plate and wrap in aluminum foil.
Heat once again to a medium heat.
Whisk the corn starch and water together until it is completely dissolved and pour into the gravy.
Bring the gravy to a boil to thicken and season with more salt and pepper if necessary.
Slice the pork line and serve it with the gravy. I garnished mine with fresh chopped parsley.