Preheat the oven to 350 ̊. Toss the squash, 2 tablespoons vegetable oil, ½ teaspoon each cumin and chili powder, the salt and several grinds of pepper on a rimmed baking sheet. Roast, tossing once, until browned and tender but not falling apart, 25 to 30 minutes.

Meanwhile, heat the remaining 2 tablespoons vegetable oil in a large skillet over medium heat. Add the onion and cook, stirring it around, until lightly browned and tender, about 10 minutes. Stir in the black beans and the remaining ¼ teaspoon each cumin and chili powder. Cook until the beans are heated through and well combined, about 2 minutes. Remove from the pan and set aside on a plate. Pour the enchilada sauce into the skillet, reduce the heat to low and warm through.

One at a time, hold the tortillas over a stovetop burner over medium heat to brown slightly, about 30 seconds per side. Set aside.

Pour 2 cups of the enchilada sauce into a 9 x 13-inch baking dish. To assemble the enchiladas, dip a tortilla into the remaining sauce, then lay on a plate. Sprinkle some cheese down the middle, followed by some of the bean mixture and finally some of the roasted squash. Roll it up tightly, then place seam-side down in the baking dish. Repeat with the rest of the tortillas. If you have any extra pieces of squash, tuck them in between the enchiladas. Be sure to save a little cheese for topping!

Pour the rest of the sauce over the enchiladas, then top with the remaining cheese. Give it a final sprinkling of chili powder, then bake until hot and bubbly, 20 to 30 minutes. Remove from the oven and let sit 15 to 20 minutes before serving. Top with cilantro.