To cook your own black beans: Rinse 1 pound of beans in a strainer and check for stones and dirt clumps. Place them in a large pot with 9 cups of water, 1 chopped onion, 4 cloves of minced garlic, 1 dried chipotle (optional but good), 2 bay leaves and 1 teaspoon of salt. Bring to a simmer and cook on low heat for about 2 to 2-1/2 hours.

During the last 30 minutes, add 1 tablespoon of cider vinegar and 1 more teaspoon of salt. Continue to cook until the beans are tender. You'll have about 2 cups more beans than needed here. If you cook your own beans, add about 15 minutes to the preparation time and 2 1/2 hours to total time. If you use canned black beans, drain and rinse them first.

For the Vegetable Layer: Heat the olive oil in a wide skillet over medium heat and cook the onion just until softened, about 4 minutes. Meanwhile, remove the seed pods from the poblano chiles by cutting around the stems. Cut the chiles into strips and dice. Add them to the onion and continue to cook. After 5 minutes, add the bell pepper, corn and zucchini. Cook until the zucchini is tender, a couple of minutes longer. Season with salt and pepper to taste. Set aside.

For the Salsa Layer: Combine the onion, tomatoes, jalapenos and cilantro. Season with the chile powder and salt.

For Assembly: Drain off any excess liquid from the black beans and roughly puree them in a food processor. Set aside.

Oil a 15- by 10-inch jellyroll pan (a 12-inch paella pan also works well). Heat the oven to 350 degrees. Lay out the first tortilla in the middle of the baking dish. Spread on a thin layer of pureed black beans, about 1/2 cup. Next add a layer of sauteed vegetables, about 1/2 cup of grated cheese and a layer of salsa.

Repeat layering. As you build, lightly press in the middle. The torta tends to bunch up in the middle. Don't press too hard or overwork when spreading. Just lightly spread on each layer. Finish with the sixth tortilla, spread on the last layer of beans, a layer of salsa and 1 cup of cheese.

Bake until the cheese is bubbly and beginning to brown, about 35 minutes. Allow the torta to rest about 15 minutes before serving.

This recipe yields 6 to 8 servings.

Each of 8 servings: 409 calories; 829 mg sodium; 42 mg cholesterol; 19 grams fat; 10 grams saturated fat; 41 grams carbohydrates; 21 grams protein; 9.79 grams fiber.