Follow these detailed, step-by-step instructions to achieve perfectly crispy skins and a flavorful, creamy filling. The process is straightforward and involves two baking stages for maximum deliciousness.

Step 1: Prepare and First Bake the Sweet Potatoes
Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper for easy cleanup. Thoroughly scrub the sweet potatoes under running water to remove any dirt. Pat them completely dry with a paper towel; a dry surface is key to a crispy skin. Using a fork, pierce each potato 5-6 times all over. This allows steam to escape during baking, preventing the potatoes from bursting.

Rub the entire surface of each potato with olive oil, then sprinkle generously with 1/2 teaspoon of salt and 1/4 teaspoon of black pepper. Place the prepared potatoes on the lined baking sheet and bake for 45-60 minutes. The cooking time will vary depending on the exact size of your potatoes. They are ready when a knife or fork can be inserted into the center with no resistance. The flesh should be completely soft and tender.

Step 2: Prepare the Sweet Potato Skins
Once baked, carefully remove the potatoes from the oven and let them rest on the baking sheet for about 10-15 minutes, or until they are cool enough to handle safely.

Once cooled, slice each potato in half lengthwise. Using a spoon, carefully scoop out the cooked flesh from the center of each half, leaving about a 1/4-inch thick border of potato attached to the skin. This border is crucial as it provides structure and prevents the skin from collapsing. Be gentle during this process to avoid tearing the delicate skins. Place the scooped-out flesh into a large mixing bowl. Arrange the hollowed-out potato skins face-up back on the baking sheet.

Step 3: Create the Savory Filling
To the bowl with the scooped-out sweet potato flesh, add the black beans, corn, diced red onion, and the optional shredded beef or ham. Add the remaining 1/2 teaspoon of salt, 1/4 teaspoon of black pepper, ground cumin, chili powder, and garlic powder.

Using a fork or a potato masher, gently mix and mash all the ingredients together. Be careful not to overmix; you want to maintain some texture from the beans and corn. The mixture should be well-combined but not a completely smooth puree. Taste the filling and adjust the seasonings if necessary.

Step 4: Stuff and Second Bake
Evenly divide the filling mixture among the 8 hollowed-out sweet potato skins, mounding it slightly in the center. Don’t be shy—pack it in!

Sprinkle the shredded cheese generously over the top of each stuffed skin.

Return the baking sheet to the 400°F (200°C) oven. Bake for another 15-20 minutes, or until the filling is heated all the way through and the cheese is completely melted, bubbly, and slightly golden on top. For extra-crispy cheese, you can switch the oven to the broil setting for the last 1-2 minutes, but watch it very closely to prevent burning.

Step 5: Garnish and Serve
Remove the stuffed sweet potato skins from the oven. Let them cool for a minute or two before garnishing. Top each skin with a dollop of Greek yogurt or sour cream, a sprinkle of fresh cilantro, and any other desired toppings like sliced jalapeños or avocado. Serve immediately with lime wedges on the side for squeezing.