Prepare Filling

1. Boil chiles and tomatillos in salted water, whole, for 1 hour
2. Remove from water and reserve 2 tbsp of cooking liquid with tomatillos
3. Heat 1 tbsp olive oil in medium saucepan over medium heat. Sauté onions 10 minutes until translucent and lightly-browned
4. Transfer to blender with tomatillos and reserved cooking liquid, jalapenos, garlic cloves, 1 tbsp olive oil, and 1 cup of chicken stock. Blend until almost smooth
5. Add cilantro leaves and blend for 15 more seconds
6. Transfer to medium saucepan and simmer 5 minutes on medium-high heat to reduce
7. Add shredded, cooked chicken, simmer 5 minutes longer. Remove from heat while assembling masa dough

Assembling Masa Dough

1. Heat 2 tbsp lard in small saucepan to melt
2. Place masa in medium bowl, and mix in melted lard. Slowly mix in 1¼ - 1½ cups of chicken stock, until it reaches the consistency of play-dough
3. Knead 10-20 minutes
4. Spread 2 tbsp masala dough onto one side of banana leaf, leaving about 1" from the top and both lengths
5. Top with 1-2 tbsp of chicken in tomatillo sauce
6. Fold banana leaf over the contents twice, then fold vertical lengths in towards center. Fold down once more to seal in sides. Cut off excess leaf if needed
7. Steam tamales in steam basket insert or a bamboo steamer, over simmering water, covered, for 1 hour
8. Serve immediately in banana leaves