Step 1
Place corn husks in a bowl cover with boiling water and soak for a few hours. Drain place on a work surface and cover with a clean damp towel.
Step 2
Place chicken in a pot season with salt and cover with water. Bring to a boil over medium-high heat reduce heat cover and simmer until chicken is cooked through 20 to 25 minutes. Drain chicken and shred with 2 forks.
Step 3
Heat a griddle over medium heat and toast ancho and mulato chiles until fragrant 3 to 5 minutes. Place in a bowl and cover with boiling water. Soak until soft about 25 minutes. Combine ancho and mulato chiles garlic cumin seeds and about 1/2 cup of the soaking water in a blender; blend until a thick smooth mole-like sauce forms adding more water if necessary.
Step 4
Heat 1 tablespoon lard in a saucepan over medium heat and add the sauce; cook for 3 to 5 minutes. Add shredded chicken and cook until flavors are combined and chicken is heated through about 5 minutes.
Step 5
Place remaining lard in a large bowl; beat with an electric mixer until creamy. Add masa harina chicken broth baking powder and 1 1/2 teaspoon salt and beat until all ingredients are well combined. Test if the masa is ready by dropping a small ball of masa into a glass of cold water; if it floats it's ready if not keep working the dough a little longer.
Step 6
Select 1 wide corn husk. Spread about 2 tablespoons masa mixture onto the the corn husk filling it up to 2 inches from the bottom and 1/4 inch from the top. Add 1 tablespoon of the chicken filling in the center of the masa mixture. Fold sides of husk together one over the other. Fold the bottom of the husk over the seam of the 2 folded sides. Repeat with remaining husks.
Step 7
Place a steamer insert into a saucepan and fill with water to just below the bottom of the steamer. Bring water to a boil. Add tamales with the open side up and cook until filling is heated through and separates from the husk about 1 hour. Let tamales rest for 15 minutes before serving.