It is safe to cook a frozen pork roast using an oven or a grill. Frozen pork should not be cooked in a slow cooker.
A well-wrapped pork roast can be stored in a freezer for up to 6 months according to the National Pork Board. Cooking frozen pork without defrosting it first increases cooking time by approximately 50 percent. A meat thermometer can be used to ensure thorough cooking.
The ideal way to thaw frozen pork is in its original wrapping inside the refrigerator. It can also be defrosted using a microwave but needs to be cooked as soon as it has thawed when this method is used.