In a large bowl, beat the lard, either by hand or using an electric mixer until it changes to a whiter color.
Add the cornflour and mix well. Before adding the pork cracklings, place them inside a plastic bag, and using a kitchen mallet or wooden rolling pin, slightly smash them. And add them to the dough mix. Then, stir in the black beans, and with your hands or a wooden spoon, mix them with the corn dough
Once you have the corn flour, lard, beans and pork crackling integrated, slowly pour the chicken broth into the mixture. Mix using your mixer or with your hands, now taste to check if it needs salt. Season with salt if needed. Since the beans and pork cracklings are already seasoned, you have to be careful when adding salt. Remember that steaming the tamales reduces a little bit of the saltiness. Your dough will look a little bit like cookie dough when ready.
To prepare the banana leaves for wrapping your black bean tamales, first, you need to remove the ribs of the banana leaves using some kitchen scissors, cut the leaves into pieces. To soften them, we will place them, one by one, over an open flame on your stove. The shiny side of the leaf will be facing down, and at the contact with the flame, the upper side will start changing to a bright green color. Make sure you move the leaf all over to soften it completely. Once all the leaves are ready, rinse them with warm water to clean, and pat dry with a paper towel.
To form the black bean tamales, Place 4 tablespoons of the dough mixture in the center of the banana leaf if you are using the Hoja Santa, add a little piece on top of the dough. Wrap the tamal, fold the first one side of the center, and the other side towards the center, and do the same
process with the ends of the banana leaf in order to form a small rectangular package.
Place already formed tamales into Tamal Steamer or big pot. If you don’t have a Tamal Steamer, you can improvise, by placing large pieces of crinkled aluminum foil at the bottom of the pot and then adding some of the leftover banana leaves or ribs to form a barrier to avoid contact with the bottom of the pot.
Add 2 ½ cups of hot water to the pot, cover the tamales with more banana leaves or with aluminum foil. Place the lid and cook and medium heat for one hour and 15 minutes. Wait at least 20 minutes before serving, to allow the tamales to cool down, and the dough to firm up. These tamales are usually served with a tomato sauce. Cook 1 large tomato and 2 habanero peppers until soft, discard cooking water, place tomatoes and peppers in your blender, process until smooth, season with salt.Enjoy your black bean tamales with a tomato sauce.