Marinate the roast in orange juice and 4-5 large garlic cloves for a minimum of 2 hours and up to overnight. Depending on the size of the roast, marinate in a sufficient amount of orange juice - enough to cover.

Put all purpose flour on a large dinner plate/ baking sheet. Dredge roast in the flour. Pour olive oil in a deep skillet, enough to cover the bottom of the skillet. Heat oil on medium-high heat until hot, the bottom of a wooden spoon should create tiny bubbles when placed in the oil.

Sear the pork roast in the oil on all sides, turning after 3-4 minutes. This should create a chestnut brown color on all sides. Remove roast from the pan, place on a plate and sprinkle with salt and pepper. Deglaze the skillet with the Marsala wine, scraping the bottom and sides with a wooden spoon. After one minute, enough time to burn off the alcohol of the wine, add orange juice to pan.

Place the roast back in the pan at Medium-Low heat. Cover the roast, leaving the lid slightly askew. If the liquid becomes too dense, add water. Cook for 25-30 minutes, turn once after 15 minutes.

Once the pork is done, place on a warm platter and let it rest for about 5 minutes. Spoon some of the liquid over the roast, sprinkle with orange zest and parsley and serve immediately.