Start by finely chopping the onion and draining your black beans. Mix the beans with chili powder, cumin, garlic powder, and salt in a bowl. This seasoning layer is key to a flavorful filling.
Warm your corn tortillas until flexible. Spoon the seasoned black bean mixture down the center of each tortilla, then sprinkle generously with shredded cheese. Fold carefully to keep the filling inside.
Arrange tacos on a parchment-lined sheet pan. Bake at 400°F (200°C) for about 8–10 minutes, then check the undersides. If they’re not golden yet, give them a few more minutes. Flip carefully with a spatula to crisp the other side.
Once out of the oven, add fresh cilantro, a dollop of sour cream, or a squeeze of lime juice. This step brightens the flavors and makes them visually appealing.