Prepare the potatoes. In large nonstick skillet, heat the oil until shimmering. Add the potatoes and onions and toss to coat. Stir in seasoning. Cover and cook so that potatoes will steam. Cook until potatoes are tender, about 20 minutes.
Remove the cover, and continue cooking, stirring occasionally until the potatoes develop a crisp crust on the outside.
Divide the potatoes into six dishes. Top with carnitas, shredded cheese, tomato, sour cream, and green onion.
Promptly store leftovers in an airtight container in the refrigerator, for up to 4 days.Nutritional values are approximate and based on 1/6 the recipe.