Place the corn husks in a large bowl and fill with hot water. Place a heavy mug or something on top of the corn husks to help them stay submerged. Set aside for an hour to soften.
Make the dough
In a large bowl, add the instant corn masa flour (I used MASECA), salt and baking powder. Mix together with a fork.
Add in the oil and broth. Mix everything together using your hands until the mixture forms a wet dough. Cover the dough with kitchen towel and set aside to rest for 30 minutes. Meanwhile, make the filling.
Make the filling
Cut the cheese into 24 strips. Set aside.
Turn the oven broiler on high. Place the peppers on a large baking sheet and broil them on the top rack for 3 to 5 minutes per side.
Once the skin of the peppers is bubbly and a little charred, remove the baking sheet from the oven and cover with aluminum foil. Set aside to let the peppers "sweat" for 5 minutes.
Uncover and carefully peel the skin off of the peppers. Remove the seeds and cut the peppers into thin strips.
Fill and wrap the tamales
On a large corn husk with the pointy side facing away from you, spread a heaping spoonful of the prepared masa onto the bottom half of the husk using the back of your spoon.You want to have a thin layer of masa on the corn husk, but not thin enough that it’s transparent and rips. If spreading the masa with the back of a spoon is too hard, you can spread and flatten the dough onto the corn husk using your fingers.
Fill with 2 or 3 strips of roasted chiles and a portion of cheese.
Fold the long edges of the corn husk together like a book. Then fold over the remaining edge once more.
Fold in the pointy edge and secure the whole thing with a tie made from a thin strip of corn husk. Repeat with the remainder of the masa.
Steam the tamales
Fill the bottom of the steamer pot with water cover with the steamer insert. Place the tamales in the steamer with the open end facing up, making sure to lean them against the side of the pot so they don't fall down.
Cover and place steamer over medium-high heat. Steam for 60 to 90 minutes, until the tamale dough is cooked through. Remove tamales from steamer, let sit for 3 minutes, then serve.
Leftover tamales can be stored in the fridge for up to 10 days.To freeze, let tamales come to room temperature. Place in a freezer-safe zip-top bag and freeze. When ready to eat, let frozen tamales thaw completely in the fridge or defrost in the microwave. Reheat on the stove or in the microwave until completely warm.