In a large saucepan, cover the pork with water and add 1 garlic clove, 1 onion quarter and 1/2 teaspoon salt. Bring to a boil, cover and simmer until pork is tender, 45 to 60 minutes. Shred meat, reserving the stock.
Toast the chiles and place in a bowl, cover with warm water and soak for 20 minutes. Meanwhile, roast the tomatoes, peel and Purée in a blender. Roast the other onion quarter, 2 cloves garlic, marjoram, peppercorns and cloves.
Drain the chiles and transfer to a blender. Add the roasted onion, garlic, marjoram, peppercorns, cloves and 1 cup of the reserved stock, then Purée until smooth.
Melt 1 tablespoon lard in a skillet and sauté the chile Purée for 5 minutes. Add the puréed tomatoes and sauté for another 5 minutes; add the pork, stir and cover. Lower the heat and cook for 10 minutes.
Hold banana leaf directly over the heat for 5 seconds. Cut into 5-inch squares.
Knead masa with 2 tablespoons lard for 5 minutes.
Grease one side of the banana leaf. Place a 3-inch square of masa on the lard and top with 1 1/2 tablespoons of pork mixture. Fold opposite edges of leaf towards the center and do the same with other edges to form a closed rectangle. Use strips of leaf to tie and secure. To cook, steam for about 20 minutes.Makes 4