Prepare the corn husks: Add the corn husks to a large bowl or pot. Pour enough hot water over the corn husks to cover them completely. Cover the bowl with aluminum foil and let them soak for 1 hour to soften them up. Meanwhile, make the tamale dough and prepare the filling.
Make the dough: In a large mixing bowl or pot, add the masa harina, salt and baking powder. Mix with your hands to combine. Add the canola oil and mix together, working the dough through your fingers until everything is well combined and incorporated. The dough should feel a little crumbly, almost like wet sand, and should lightly hold it's shape when pressed together.
Add the broth and mix for about 3-5 minutes until the dough is fairly wet and well saturated. The dough should be soft and spreadable like thick hummus. If the dough is too dry, add more broth. If it's too wet, add more masa harina. Cover and set aside.
Roast the peppers: Place the poblano peppers on a baking sheet under the broiler or directly under an open flame. Roast until all the sides are blackened and blistered. Transfer them to a large bowl and cover with plastic wrap. Let them sit for 10 minutes.
Using your fingers, rub off the blackened skins. Slice the peppers open, remove the stems, seeds, and large veins, then slice into strips and set aside.
Finish prepping the corn husks: Drain the water from the corn husks and pat them dry. Remove and discard any corn silk that may be on the husks. Lay the husks flat onto a baking sheet for easy access.
Spread the masa: Grab a corn husk and identify which is the smooth side and which is the side with ridges. Place the smooth side face up into your palm or on a plate. Using a large spoon, grab a heaping spoonful of masa and place it in the middle of the corn husk. Using the back of the spoon, spread the masa in a thin layer to create rectangle shape, leaving the top 1/3 of the corn husk empty. (see post above for step-by-step photos)
Add the filling: Place one stick of cheese and a few strips of roasted poblano peppers into the center of the corn husk.
Fold: Fold together the long edges of the corn husk like a book, and then fold it once more. Fold the pointy edge over so that only one side of the corn husk is open and exposed. Place in a bowl with the open end facing up, making sure to lean them against the side so it doesn't fall down. Repeat until all the tamales have been filled and assembled.
Prepare the steamer pot: Fill the bottom of the steamer pot with water and 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.
Steam: Cover tightly with the lid and place the steamer over high heat. Bring the water in the steamer pot to a boil (you should be able to hear it bubbling), then reduce the heat to low, and cook for 1 hour and 15 minutes.
Rest and serve: Carefully transfer the tamales to a baking sheet or serving platter and let them sit and cool slightly for 10 minutes. They may be a little squishy when you first take them out of the steamer, but will quickly firm up once they have time to cool. Serve and enjoy!
Notes
Cheese: Other cheese that work great include pepper jack, Chihuahua, Oaxaca, or your favorite melting cheese.
Storage: Leftover tamales can be stored in the fridge for up to 1 week.
Freezing: To freeze, place cooked and cooled tamales in an airtight container or zip-lock bag and freeze for up to 6 months.
Reheating: You can re-steam the tamales for 15 minutes in a steamer pot, heat them in a 350°F oven for 10 minutes, heat them on a hot griddle for 2 minutes on each side, or microwave them in batches for 1-2 minutes on high.