In a mixing bowl, combine the masa harina, warm water, vegetable shortening, baking powder, and salt. Mix until well combined, then cover and let rest for 30 minutes.
In a skillet, heat the olive oil over medium heat. Add the diced vegetables and garlic, and sauté until soft, about 5 minutes.
Add the chili powder, cumin, smoked paprika, salt, and pepper, and sauté for another minute.
Add the black beans, cilantro, and lime juice, and stir to combine. Remove from heat.
To assemble the tamales, spread a thin layer of the masa dough onto a soaked corn husk, leaving a border of about 1 inch on each side.
Spoon a small amount of the vegetable filling onto the center of the dough.
Roll the corn husk around the filling, using the border of masa dough to seal the tamale.
Tie each end of the tamale with kitchen twine.
Place the tamales in a steamer basket over boiling water. Cover and steam for 1 hour.
After 1 hour, remove the tamales from the steamer and let cool for a few minutes before unwrapping.
Serve hot, garnished with additional cilantro and lime wedges if desired.