In a medium pot over medium-high heat, add the oil and sear the chuck roast on each side.
Remove the roast and set it aside. Add in the chili peppers, tomatoes, cinnamon sticks, cumin, oregano, salt, and pepper and cover with water. Bring to a boil then simmer for about 10 minutes.
Pour the contents of the pot in a blender (reduce water if needed). Blend the sauce for 30-60 seconds until smooth.
Add the roast into the pot and pour the sauce overtop. Let the pot simmer for 2-3 hours or until the roast is fully cooked and tender.
Once the roast is cooked, remove it from the pot and shred the meat with two forks. Add the meat back into the pot and stir into the sauce.
Preheat the oven to 400℉.
In a baking dish lined with parchment paper, place the bottom half of the rolls in the dish followed by the shredded beef. Add a little extra sauce if needed.
Sprinkle the oaxaca cheese on top of the beef and place the top half of the rolls on top.
Baste additional sauce on top of the rolls and sprinkle red pepper flakes on top (if desired).
Bake the rolls in the oven for 10-15 minutes. The cheese should be stretchy and melty.
Remove the rolls from the oven and allow them to cool for 5 minutes. Sprinkle with cilantro before serving.