To make the salsa and filling, preheat the broiler.
Line a baking sheet with foil and put the tomatoes and chiles on it. Rub 1 tablespoon of the oil over the tomatoes and chiles, and sprinkle with salt and pepper. Broil, turning as needed, until the tomatoes and chiles are tender and their skins have charred, about 10 minutes for the habanero, 15 minutes for the Anaheim chiles and 20 minutes for the tomatoes. When the Anaheim chiles are done, transfer them to a bowl, cover with plastic wrap, and set aside until cool enough to handle. When the habanero and tomatoes are done, transfer to a plate and let cool slightly. Peel, seed, and coarsely chop the Anaheim chiles; set aside.
Meanwhile, remove the leaves from the cilantro and place the stems in a blender.
Coarsely chop the leaves and reserve in a medium bowl. Add the whole garlic clove, the broiled tomatoes, habanero, and any accumulated juices to the blender and blend until smooth. Season the salsa to taste with salt. Set aside.
Heat a large heavy nonstick skillet over medium heat. Add
2 tablespoons of the oil, then add the potatoes and cook for about
5 minutes, or until they are beginning to soften. Add the zucchini, onion, and the chopped garlic and sauté for about 5 minutes, or until the potatoes are tender. Stir in the chopped Anaheim chiles and 1⁄4 cup of the salsa and season to taste with salt. Set aside to cool.
To assemble the enchiladas, preheat the oven to 450°F. Line a small baking sheet with paper towels.
In a small skillet, heat the remaining 4 tablespoons olive oil over medium heat. Add 1 tortilla to the pan and cook for about 20 seconds per side, or until just pliable. Using tongs, transfer the tortilla to the paper-towel-lined baking sheet to absorb any excess oil. Repeat with the remaining tortillas, layering them between paper towels.
Spoon about 1⁄3 cup of the potato mixture over the bottom third of one tortilla, then roll up and place seam-side down in a 13x9-inch baking dish. Repeat with the remaining tortillas and filling.
Bake the enchiladas, uncovered, for about 10 minutes, or just until heated through. Reheat the remaining salsa.
Drizzle about 2⁄3 cup of the remaining salsa over the enchiladas, then sprinkle the cheese, scallions, and reserved cilantro leaves over the top. Serve with the sour cream and pass the remaining salsa at the table to spoon onto plates when serving.
: The salsa and the vegetable filling can be made up to 1 day ahead, covered separately and refrigerated. Rewarm the salsa over medium-low heat before serving.