Preheat oven to 400 degrees and arrange shells in a 9x13 baking dish.
Brown ground beef over medium heat. Breaking up meat as it cooks. In a small bowl, combine salt, pepper, chili powder, smoked paprika, onion powder, garlic powder, cumin, and cornstarch. Sprinkle over ground beef and stir. Bring to simmer and stir in drained black beans. Heat until beans are tender.
Evenly distribute ground beef and beans into shells. Top with shredded cheese. Bake for about ten minutes, or until cheese is melted and shells have started to crisp. While tacos are baking, prepare toppings and spicy sour cream.
Top with preferred toppings and serve immediately.
Stir sour cream and hot sauce together until well combined.