Preheat your oven to 375°F (190°C) so that it’s ready when you’re finished assembling the enchiladas.
In a large skillet, heat the olive oil over medium heat. Add the chopped red onion and red bell pepper. Sauté for about 3-4 minutes until they start to soften. Then add the chopped broccoli and cook for another 3 minutes. Finally, stir in the baby spinach, salt, cumin, chili powder, and garlic powder. Cook until the spinach is wilted, which should take about 2 minutes. Remove from heat.
Add the drained and rinsed black beans to the sautéed vegetable mixture. Stir gently to combine, ensuring that the beans remain intact.
In a baking dish, spread about ½ cup of enchilada sauce on the bottom. Take one tortilla and spoon a generous amount of the black bean filling onto the center. Roll it up tightly and place it seam-side down in the baking dish. Repeat this process with the remaining tortillas and filling.
Once all the enchiladas are in the dish, pour the remaining enchilada sauce over the top, ensuring each enchilada is well-coated. Sprinkle the shredded cheddar cheese evenly over the sauce.
Cover the baking dish with aluminum foil and bake in the preheated oven for 20 minutes. After that, remove the foil and bake for an additional 10-15 minutes, or until the cheese is bubbly and lightly golden.
Once baked, remove the enchiladas from the oven and let them cool for a few minutes. Serve hot with your favorite toppings such as avocado, cilantro, or a dollop of sour cream.