01 -
Set oven temperature to 425°F and position rack in the middle.
02 -
In a mixing bowl, toss diced sweet potato with olive oil, ground cumin, smoked paprika, salt, and black pepper until evenly coated.
03 -
Spread seasoned sweet potatoes in a single layer on a baking sheet. Roast in the oven for 25 to 30 minutes, stirring halfway through, until tender and caramelized.
04 -
Heat a medium saucepan over medium heat, add black beans and corn, cooking for 4 to 5 minutes while stirring occasionally.
05 -
Remove from heat and stir in chopped cilantro and lime juice. Season with salt and black pepper to taste.
06 -
Layer each tostada shell with a generous portion of the black bean and corn mixture, followed by the roasted sweet potato cubes.
07 -
Top each tostada with sliced avocado and sprinkle with feta cheese if using. Serve immediately with hot sauce on the side.