1 pound banana leaves -- thawed or frozen (or corn husks) 2 cups (heaping) corn flour 2 1/2 cups warm chicken stock or water 1/2 pound lard 2 cups pureed cooked or canned pumpkin 1 1/2 teaspoon ground canela (cinnamon) 3 ounces piloncillo -- grated or crushed OR 1/2 cup dark-brown sugar, firmly packed salt ***Bean Filling*** 2 cups water 2 teaspoons anise 2 pasilla de Oaxaca chiles, dried chipotle chiles, or canned chipotles in adobo sauce 2 1/2 cups cooked or canned black beans, drained 5 cloves garlic, peeled 2 tablespoons lard salt
Prepare Bean Filling: Put water in small pan, trim leaves into 12 to 14 rectangles, each about 14x11 inches. Save some of the longer trimmings for ties.
Mix corn flour in a bowl or pot with enough warm stock to make soft but not sticky dough. Beat lard in separate large bowl on medium speed until very light and fluffy.
Add corn flour mixture and pumpkin puree to lard little at time, beating on medium speed and scraping down as needed. Mixture should be as light as butter cream.
Beat in cinnamon, piloncillo and salt to taste.
Place 1 or 2 banana leaf rectangles flat on work space (or soaked corn husks). Tear off some long, thin strips from reserved banana leaf trimmings. Place 2/3 to 1 cup corn flour mixture in center of leaf and with spatula or fingers spread into 3x4x1/2-inch thick oval.
Place 1 heaping tablespoon Bean Filling in center of oval. Fold left and right edges of banana leaf toward center to meet, overlapping little to cover filling, then fold top and bottom edges to center to make a neat, flat package about 4x5 inches. Fasten by tying with thin strip of banana leaf. Repeat with remaining banana leaves, masa and filling.