Remove pork roast from package, and rinse with warm water; drain and pat dry with paper towels. Using two forks, break pork roast into chunks.
Sauté onion in hot oil in a large skillet over medium-high heat 3 minutes or until tender. Stir in mojo criollo sauce and roast. Cook 1 to 2 minutes or until thoroughly heated. Serve over Black Beans 'n' Spuds. Garnish, if desired.