Preheat the oven to 450 degrees F, ensuring a rack is positioned in the center of the oven. Gather & prep all ingredients according to ingredients list.
Add 1 tablespoon of the olive oil to a medium skillet over medium heat. Once hot & shimmering, add the onion. Season with 1 teaspoon kosher salt. Cook, stirring occasionally, until translucent & fragrant, 3-4 minutes.
Stir in the garlic & chipotle. Cook just until fragrant, about 30 seconds. Add in the chili powder, ground cumin, smoked paprika, & tomato paste. Stir, coating the onion. Cook 1-2 minutes longer, until very fragrant.
Add black beans to the skillet, stirring to combine with the aromatics. Cook, stirring occasionally, until warm, 1-2 minutes. Add vegetable stock, increasing heat to bring the mixture to a simmer. Use a spatula or wooden spoon to mash the black beans slightly, binding everything together. If needed, cook 1-2 minutes longer to thicken slightly. Squeeze the lime juice over the black bean mixture. Taste & season with S&P as desired. Remove from the heat & set aside.
Meanwhile, as the black bean filling cooks, prep the tortillas. Wrap the corn tortillas in a damp paper towel. Microwave 30 seconds to steam the tortillas, making them pliable enough for taco assembly. Remove from the microwave & set aside.
Brush the remaining olive oil across the surface of a large rimmed baking sheet. Place the warmed tortillas on the baking sheet, flipping them one or two times to get a nice light coating of oil on both sides. Spread the black bean mixture over half of each tortilla, then sprinkle the cheese over top. Fold the tortillas, creating a taco around the black bean & cheese filling. I like to carefully flip the tacos at this point, so the cheese side is facing down.
Transfer the sheet pan to the oven & bake the tacos 8-10 minutes. Remove from the oven. Working quickly & carefully, use a spatula to flip the tacos. Return to the oven & bake 8-10 minutes longer, until golden & crisp. Remove from the oven & allow to cool 2-3 minutes – the tacos will get even crispier as they cool.
Serve the crispy black bean tacos warm, finishing with toppings of choice – cashew crema, chopped cilantro, lime juice, salsa, or any other toppings your taco-lovin’ heart desires. Enjoy!