Place chiles and garlic in microwave safe bowl. Microwave for 1.5 minutes or until chiles are soft and flexible. Remove stems and seeds from chiles. Peel garlic. Add chiles and garlic to blender. Add remaining chile sauce ingredients to blender and blend until smooth. Set aside.
Season blade roast all over with salt and pepper. Heat lard or oil in a dutch oven over medium heat.
Sear blade roast on all sides possible until browned, about 2 minutes per side. They are a unique shape, so just do your best to get all of the sides.
Remove blade roast to plate. Add more lard to dutch oven if there is not enough left to coat the bottom of the pan. Add in chile sauce. Stir frequently until fragrant and slightly browned.
Add in broth, cinnamon sticks, and bay leaves. Stir until combined. Add blade roast to sauce and make sure liquid covers the whole roast. Refrigerate overnight or continue to next step.
Preheat oven to 250°F. Heat dutch oven with meat and marinade over medium heat until mixture begins to boil. Cover and place in oven for 6-8 hours or until meat is tender and falls off the bone. If using a crockpot, cook on low for 8-10 hours.
Remove meat to a plate and shred. Strain broth through a fine mesh strainer. Use a spoon to push as much of the chile sauce through the strainer as possible. Use a spatula to scrape the outside of the strainer. The goal is to still get as much of the sauce back into the pan, but remove any gritty pieces. Add sauce and meat back to dutch oven and return to the oven for 20 minutes or until heated through.
Assembly:
Warm tortillas. To each tortilla, add shredded meat, cheese, pickled onions, avocado slices and cilantro. Serve with lime wedges.
Freezing Instructions:
Place meat with enough sauce to cover the meat in a freezer zippered bag or vacuum bag. Squeeze the air out and freeze flat on a sheet pan. Freeze for up to 6 months. Thaw and reheat using the boil-in-bag method (if stored in a heat-safe bag) or reheat in a pan on the stove.