Vegetarian Enchiladas with Butternut Squash and Black Beans

extra-virgin olive oil

small red onion, diced

1/2-inch-cubed butternut squash (about 1 small, 1 1/2-pound squash)

garlic, minced (about 1 tablespoon)

ground chipotle chili powder (reduce to 1 or 1/2 teaspoon if sensitive to spice)

ground cumin

kosher salt

black pepper

Simple Truth Black Beans, rinsed and drained

red enchilada sauce or 1 1/4 cups homemade red enchilada sauce

freshly grated sharp cheddar, Monterey jack, pepper jack, or similar cheese

taco-sized (about 8-inch) whole wheat low-carb tortillas (I used La Banderita brand)

Optional, for serving: sliced avocado, chopped fresh cilantro, additional shredded cheese, additional chopped red onion, nonfat sour cream or plain Greek yogurt