If want to cut down on some of the preparation time, buy grated cheese and pre-peeled and seeded squash, to be cut into 3/4-inch pieces (you will need 5 to 6 cups).
For the vegetables:
- 1 (2-pound) butternut squash, seeds removed and cut into 3/4-inch pieces
- 1 large onion, cut into 8 wedges
- 2 cloves garlic
- 2 tablespoons olive oil
- 1/2 teaspoon salt
- 1/8 teaspoon black pepper
For the sauce:
- 1 (28-ounce) can whole tomatoes with juice
- 1 tablespoon ancho chili powder, or regular chili powder
- 1/2 teaspoon oregano
- 1/2 teaspoon cumin
- 1/2 teaspoon salt
- 1 tablespoon olive oil
For the filling and assembly:
- About 1/4 cup olive oil, to brush on the tortillas
- 1 (15-ounce) can black beans, rinsed and drained
- 12 (7-inch) corn tortillas
- 2 cups grated Monterey Jack cheese
For the garnishes (optional):
- 1 handful cilantro leaves
- 1 avocado, sliced
- 6 radishes, thinly sliced
- 1/4 red onion, sliced
- 1/2 cup sour cream, thinned with milk to the consistency of thick cream
1 Preheat the oven to 450ºF.
2 Roast the squash, onion, and garlic: On a large, rimmed baking sheet, mound the squash cubes in the center and place the onion wedges and garlic on the side.
Sprinkle everything with the olive oil, salt, and pepper. Toss to coat the vegetables and spread them evenly over the baking sheet, segregating the onion and garlic alongside the squash. Bake for 25 minutes, or until tender.
Remove the pan from the oven, and reduce the oven temperature to 375ºF. Let the squash and onion cool slightly on the baking sheet.
3 Make the sauce: In a blender, combine the tomatoes, chili powder, oregano, cumin, and salt. Add the garlic and half of the roasted onion slices. Puree until smooth.
In a medium skillet set over medium heat, add 1 tablespoon olive oil. Once the oil shimmers, add the pureed sauce to the pan and bring to a simmer. Cook, stirring often, for 5 minutes. Set aside.
4 Make the filling: Transfer the squash and the remaining onion slices to a bowl. Separate the onion slices. Stir in the drained beans. Taste and add more salt, if you like.
5 Warm the tortillas: Using a pastry brush, brush both sides of each tortilla with oil. Place up to 6 tortillas in a stack on a microwave-safe plate.
Loosely cover and microwave in 30-second intervals until the tortillas are warm and pliable; this takes about 1 minute.
Wait to repeat the process with the remaining 6 tortillas until you’ve filled the first batch.
6 Assemble the enchiladas: Spread a thin layer of sauce over the bottom of a 9x13-inch baking dish.
Dip one tortilla in the sauce and set it on a plate. Place about 1/3 cup of the filling in a line down the center of the tortilla. Sprinkle with about 1 tablespoon of cheese.
Roll up the tortilla to enclose the filling and set it in the baking dish with the seam side down.
Repeat until all 12 of the tortillas are filled. Pour the remaining sauce over the enchiladas and sprinkle the remaining cheese on top.
7 Bake the enchiladas: Bake for 25 minutes at 375ºF, or until the cheese melts and the enchiladas are hot all the way through. Serve with the garnishes of your choice.