Preheat the oven to 450 degrees F and position a rack in the center of the oven. Gather and prep all ingredients.

Add 1 tablespoon of olive oil to a medium skillet over medium heat. Once hot, add the onion and season with salt. Cook until translucent and fragrant, 3-4 minutes.

Stir in the garlic and chipotle. Cook until fragrant, about 30 seconds. Add in the chili powder, ground cumin, smoked paprika, and tomato paste. Cook for 1-2 minutes longer.

Add the black beans to the skillet and stir to combine. Cook until warm, 1-2 minutes. Add vegetable stock and increase heat to bring to a simmer. Mash the black beans slightly and cook until thickened, if needed. Squeeze lime juice over the mixture and season with additional salt and pepper as desired. Remove from heat.

Wrap the corn tortillas in a damp paper towel and microwave for 30 seconds to steam them. Remove from the microwave and set aside.

Brush the remaining 2 tablespoons olive oil across a large rimmed baking sheet. Place the warmed tortillas on the baking sheet, flipping to coat both sides with oil. Spread the black bean mixture over half of each tortilla, then sprinkle with cheese. Fold tortillas to create tacos.

Transfer the baking sheet to the oven and bake the tacos for 8-10 minutes. Carefully flip the tacos and return to the oven for another 8-10 minutes, until golden and crisp. Allow to cool for 2-3 minutes.

Serve the crispy black bean tacos warm with toppings of choice.