Preheat oven to 350˚F (180˚C). Grease a 13- x 9-inch (33 x 23 cm) baking pan with three tablespoons (45 mL) of the lard. Sprinkle with a little flour and shake off any excess flour.
Peel potatoes and place in a medium bowl with cold water, then grate potatoes on the fine side of a grater or in the bowl of a food processor with the fine-shredding side of the wheel attachment. Transfer potatoes to a large bowl.
Add grated coconut, sugar, salt and 1/2 cup (125 mL) water and mix well with your hands. Add flour and remaining lard and continue mixing thoroughly.
Add black pepper, cinnamon and another 1/2 cup (125 mL) water (the consistency should feel like a pudding, add more water, if needed).
Transfer mixture to the baking pan and bake in the center of the oven for two hours (cover loosely with foil after one hour to maintain the color). Let cool to a warm temperature and enjoy.