You can cook pork from frozen in the oven, but it will take longer to cook than if it were thawed first. It's best to plan ahead and allow extra time for cooking a frozen roast. To cook a pork roast from frozen, preheat your oven to 350 degrees Fahrenheit. Place the frozen roast on a rack in a roasting pan and add water or beef broth to the bottom of the pan. Cook for about 2 hours, or until the internal temperature of the pork reaches 145 degrees Fahrenheit. Let rest for 3-5 minutes before slicing and serving. Enjoy!