• Add cumin, chili powder, onion powder, cayenne pepper, ground coriander, salt, and pepper to the chuck roast. Salt liberally and cut into large chunks. Set aside.
• Bring about 8 cups of water to a boil in a medium saucepan.
• On a cutting board, cut chiles and remove the seeds. Add oil to a frying pan and toast the chiles for 3-4 minutes, until slightly charred. Then place the chiles in the boiling water until softened, about 10 minutes.
• Add an additional tablespoon of oil to the frying pan and add sliced onions. Cook until softened and fragrant, then add peppercorns, thyme, oregano, bay leaves, cumin ginger, and a cinnamon stick. 
• Continue to cook for 4 minutes then add tomato paste and stir until paste forms then remove from heat and take out the bay leaves and cinnamon stick. Add everything left in the pan into a blender along with softened boiled chilies (don't worry about draining the peppers completely), Garlic, Chipotle Peppers in Adobo, Fire Roasted Crushed Tomatoes, and Apple Cider Vinegar. Blend together until smooth and thick.
• Add 4 tbsps of vegetable oil to a large pot and allow it to warm. Add beef chunks and sear on all sides until browned and crisp (Be sure not to overcrowd the pot, cook in batches if needed).
• Pour blended tomato/chili puree into the pot on top of the beef and add beef stock. Bring to a boil and then reduce to a simmer. Cover with a lid and cook for 2 1/2-3 hours, until beef is fork tender. 
• Taste for salt and add as needed then remove the beef and shred with a fork. Save the juices to dip the quesadilla into!

Birria Quesadillas

• Melt butter and olive oil in a pan. Dip the tortilla into the reserved juices from the pot and place into the pan.  Add 1/2 cup Mexican Blend Cheese Mixture and 1/2 cup Mozzarella (more if you'd like). Then add about 1 cup of the shredded beef on top of the cheese and place the second tortilla on top.
• Flip over in the pan and allow the second side to crisp. Remove from pan and enjoy.