Wash the peppers then dry them and use a pair of kitchen shears to cut off the stems and slice down the side. Open the peppers and scrape out the seeds.
Add them to a medium saucepan with the onion, Roma tomatoes, bay leaves, garlic, cinnamon stick, and peppercorns. Cover completely with water and bring to a boil. Cover and continue to boil over medium-high heat for 10 minutes.
While it’s boiling, sear the beef. Season each piece of the chuck roast generously on all sides with salt and pepper. Heat olive oil in a large Dutch oven over medium-high heat. Sear each side of the beef for 2-3 minutes, until they form a crispy crust on the outside. Work in batches, placing the first batch on a plate or cutting board while you finish. Working it batches helps sear the beef rather than steaming it if the pot is overcrowded.
When all of the beef is seared, turn off the heat and place all the beef back in while you finish the sauce.
Use a slotted spoon to transfer the peppers and the rest of the ingredients, including the cinnamon stick and bay leaf, to a large high-speed blender. Add 1/2 cup of the boiling liquid along with the cumin, ground cloves, vinegar, and 4 cups of beef broth. Blend on high until completely smooth, 1-2 minutes.
Pour the sauce over the beef, making sure it comes about halfway up the meat. Bring the beef Birria to a boil over high heat then turn the heat down to low and braise (just below a simmer) for 3 1/2 -4 hours.
Remove the beef to a rimmed baking sheet or large plate and shred using two forks.