These crispy sheet pan black bean tacos are filled with warmly spiced, gently mashed black beans and melty cheese, then baked until golden and crunchy. They’re an easy vegetarian dinner for four, with plenty of room for favorite toppings like guacamole, salsa, cilantro, or cashew crema.
Preheat the oven to 450°F with a rack in the center. Chop and measure the ingredients before you begin; the filling comes together quickly.
Heat 1 tablespoon olive oil in a medium skillet over medium heat. Add the diced onion and season with 1 teaspoon kosher salt. Cook, stirring occasionally, for 3–4 minutes, until translucent and fragrant.
Stir in the garlic and, if using, the chopped chipotle or adobo sauce. Cook for about 30 seconds, just until fragrant. Add the tomato paste, chili powder, cumin, and smoked paprika. Stir to coat the onion and cook for 1–2 minutes, until fragrant.
Add the black beans and stir to combine. Cook for 1–2 minutes, until warmed through. Pour in the vegetable broth and bring the mixture to a simmer. Use a spatula or wooden spoon to mash some of the beans, helping the filling bind together. Cook for another 1–2 minutes if needed to thicken. Stir in the lime juice, taste, and add more salt and black pepper as desired. Remove from the heat.
Wrap the corn tortillas in a damp paper towel and microwave for 30 seconds, until warm and pliable. Set aside.
Brush the remaining 2 tablespoons olive oil over a large rimmed baking sheet. Place the warmed tortillas on the sheet and turn them once or twice to lightly coat both sides. Spoon the black bean filling over half of each tortilla and top with shredded cheese. Fold each tortilla over the filling to form a taco. If desired, carefully flip the tacos so the cheese side faces down.
Bake for 8–10 minutes, then carefully flip each taco with a spatula. Return the pan to the oven and bake for another 8–10 minutes, until the tacos are golden and crisp. Let them cool for 2–3 minutes; they will crisp further as they rest.
Serve warm with your choice of cashew crema, guacamole, cilantro, lime juice, salsa, or other favorite toppings.