01 - Preheat oven to 325°F.
02 - Pat the beef dry and season thoroughly with salt, pepper, cumin, chili powder, paprika, and oregano on all sides.
03 - Heat olive oil in a Dutch oven over medium-high heat. Sear beef on all sides until deeply browned, developing a rich crust.
04 - Add minced garlic, beef broth, and tomato sauce around the beef. Bring to a simmer, cover tightly with lid, and transfer to preheated oven.
05 - Braise for 2 to 2.5 hours until beef is fork tender and easily shreds.
06 - Remove beef from cooking liquid and shred using two forks. Mix shredded beef back into the cooking juices to absorb flavor.
07 - Heat a nonstick skillet over medium heat. Sprinkle about 1/4 cup of the mixed shredded cheeses in a circular pattern. When cheese melts and edges begin to crisp, place a tortilla on top and press gently.
08 - Cook until cheese becomes golden and crispy, about 2-3 minutes. Flip briefly to warm the other side. Remove and keep warm. Repeat process for remaining tortillas.
09 - Fill each crispy cheese tortilla generously with shredded beef. Top with diced onion, fresh cilantro, avocado slices if using, and salsa. Serve immediately with lime wedges.