Preheat oven to 350 degrees Fahrenheit.
Heat your olive oil in a large nonstick skillet over medium heat. Add in your shallot and sauté until softened and translucent, about 2-3 minutes. Add in your zucchini, poblano, garlic, and a couple pinches of kosher salt and pepper.
Allow vegetables to soften, stirring occasionally, about 5-7 minutes. Add in your corn and chard and cook until the chard begins to wilt and the corn is warmed through, another 5 minutes.
Add your drained and rinsed black beans and cook until warmed through, about 5 minutes. If using, mix in a couple tablespoons of the enchilada sauce and stir it all together. Taste and adjust seasoning as needed. Set aside to cool slightly while you heat your tortillas.
Heat your tortillas until you get the desired charred edges and keep on a plate until all 10 to 12 are cooked. Using a 9 x 13 baking dish, add a few tablespoons of enchilada sauce and swirl around to coat the bottom of your baking dish. To prep your enchiladas, add a tablespoon or two or the veggie mix to a tortilla and roll up.
Place the rolled enchilada onto your baking dish and repeat until all the tortillas are prepped with the veggie mix. Top your enchiladas with the remaining sauce and cheese. Bake until golden and bubbly with some tortilla edges slightly crisp, about 20-30 minutes.
Cool 5 to 10 minutes before serving. Garnish with chopped fresh cilantro and serve alongside your favorite beans and rice.