For the tamales, moisten the instant corn flour with the warm water, and set aside. Beat shortening in mixer until creamy and fluffy. Fold in the corn flour and the chicken stock.
Mix well and set aside. In a blender puree huitlacoche and cilantro with a little water until smooth. Add this mixture to the dough and fold in well. Season with salt and pepper. Have cornhusks already soaking in water.
To assemble the tamales, open the corn husks and place 1 spoonful of dough in the center of the cornhusk. Fold over the sides of the husk and secure with a piece of string. Repeat the rocess until all the dough is finished. In a double boiler with a steamer insert, steam the tamales for 40 to 45 minutes.
Remove tamales from the steamer and allow them to sit for 5 minutes. Then open them and serve them with a sprinkle of cheese.