½ of a medium butternut squash, peeled and cut into ½ inch cubes (about 5 cups)
½ cup white onion, chopped
3 tablespoons olive oil
1 ½ teaspoons cumin
1 ½ teaspoons coriander
2 teaspoons plus 1 tablespoon ancho chile powder
1 teaspoon salt
2 cloves garlic, minced
2 cups tomatoes, skinned, seeded and chopped (or 1 15-ounce can fire roasted, diced tomatoes)
2 15-ounce cans black beans
1 serrano chile (if you like spicy beans)
¼ cup cilantro, chopped
12 small corn tortillas
½ cup crumbled cojita cheese (or feta)
Preheat your oven to 400 degrees. Heat a cast iron skillet over medium high. Place the jalapenos and serrano (if using) into the pan and cook until the skins are charred and blistered in spots. Remove the pan from the heat and set the peppers aside.
In a large bowl, toss the squash and onions together with 2 tablespoons olive oil. Sprinkle the cumin, coriander, 2 teaspoons of the chile powder, and 1 teaspoon salt over the squash and onions and toss until well coated. Divide the vegetables between two rimmed baking sheets and spread them out in a thin layer, so each piece has a bit of room between it and its neighbors. Place into the oven and roast for 20 to 25 minutes, or until the edges of the squash and onions begin to brown. Rotate the pans and give the vegetables a quick stir halfway through.
Meanwhile, peel, stem and seed the chiles before chopping them finely. Then, heat the remaining tablespoon of olive oil in a medium saucepan over medium high heat. Add the garlic and cook for a minute or two before pouring in the tomatoes. Allow the tomatoes and garlic to bubble briskly for five to ten minutes, or until the tomatoes reduce down to a loose sauce. Sprinkle 1 tablespoon of the chile powder over the tomatoes and then stir in the chiles and the beans with their liquid. Cook the beans over medium heat for 15 minutes, stirring carefully so you do not smoosh them. When the beans reach your preferred consistency, remove them from the heat, stir in the cilantro, and adjust the seasonings.
To assemble the tacos, spread a few spoonfuls of strained beans onto a warm tortilla. Place a mound of roasted squash and onions on top of the beans. Shower the tacos with crumbled cojita cheese, chopped cilantro, and a squeeze of fresh lime juice.