Preheat the oven to 425°F (220°C). Wash and peel the potatoes, then cut them into approximately 1-inch chunks.
For extra-crispy potatoes, place the potato chunks in a large bowl of cold water and soak for 20–30 minutes. Drain thoroughly and pat completely dry.
Toss the potatoes with 1 tablespoon of oil, about half of the chili powder, and a pinch of the salt.
Arrange the potatoes in a single layer on a large baking sheet. Roast for 20–25 minutes, turning halfway through, until golden and tender.
While the potatoes roast, heat a large skillet over medium-high heat. Add the remaining chili powder, salt, garlic powder, and black pepper. Toast for about 30 seconds, watching carefully so the spices do not burn.
Add the ground beef and cook, breaking it into small pieces, until browned and completely cooked through.
Stir in the frozen corn and water. Bring to a gentle simmer, cover, and cook for about 5 minutes, until the corn is hot and the liquid has reduced.
Divide the roasted potatoes among serving bowls and spoon the seasoned beef and corn mixture over them.
Finish each Loaded Potato Taco Bowl with shredded cheddar, guacamole, pico de gallo, sour cream, or your preferred toppings. Serve warm.