Soak the corn husks

• Place the corn husks in a large bowl of warm water and weigh them down so they stay submerged.
• Let them soak until soft and pliable, then drain before using.

Cook the pork

• Put the pork in a pot with half the onion, half the garlic and salt.
• Cover with water and simmer until the meat is tender and shreds easily.
• Shred the pork, reserving some of the cooking broth.

Make the chile sauce

• Toast the guajillo and ancho chiles in a dry frying pan until fragrant.
• Soak the chiles in hot water until softened, then drain.
• Blend the chiles with the remaining onion and garlic, cumin, oregano, salt and a little broth until smooth.

Season the filling

• Fry the chile sauce in a hot pan until it darkens slightly.
• Stir in the shredded pork and enough broth to make a moist filling.

Prepare the masa

• Beat the lard until light and fluffy.
• Mix in the masa harina, baking powder and salt, adding warm stock gradually.
• Beat until the dough is smooth and spreads easily.

Assemble the tamales

• Spread a thin layer of masa over the wide end of each drained husk.
• Spoon the pork filling in the center.
• Fold in the sides and fold up the bottom of the husk.

Steam the tamales

• Stand the tamales upright in a steamer with water below.
• Cover and steam until the masa pulls away cleanly from the husk.

Rest and serve

• Let the tamales rest briefly before unwrapping.
• Serve warm.