Adjust the oven rack to the highest position and heat the broiler. Place the poblanos and red bell peppers on a foil-lined baking sheet and broil, turning as needed, until the skins are charred and blistered on all sides, about 10 to 12 minutes.

Transfer the charred peppers to a bowl and cover tightly with plastic wrap; let them steam for about 10 minutes to loosen the skins. Peel the peppers, discard the stems and seeds, and chop the flesh into half-inch pieces.

Adjust the oven to 400°F. Heat the oil in a large skillet over medium-high heat until shimmering. Add the onion and zucchini and cook until the vegetables are softened and starting to brown, about 8 to 10 minutes.

Stir in the garlic, cumin, and coriander and cook until fragrant. Remove from the heat and stir in the chopped poblanos, red peppers, black beans, and half of the shredded cheese.

Spread a half-cup of the enchilada sauce over the bottom of a 9x13-inch baking dish. Warm the tortillas in the microwave or in a dry skillet until pliable so they don't crack when rolled.

Working with one tortilla at a time, dip it lightly into the remaining sauce to coat both sides. Place a portion of the filling in the center, roll tightly, and arrange seam-side down in the baking dish.

Top the rolled enchiladas with the remaining sauce and the rest of the cheese. Bake until the sauce is bubbling and the cheese is lightly browned, about 15 to 20 minutes.

Serve hot, topped with fresh cilantro and sour cream.