Trim any excess fat and pat the Beef Chuck dry, then season generously with Salt, Black Pepper, Ground Cumin and Mexican Oregano.
Heat a couple tablespoons of Neutral Oil in a heavy pot over medium-high heat and sear the beef on all sides until deeply browned; remove and set aside.
Lower the heat, add chopped White Onion, minced Garlic, diced Roma Tomato and sliced Jalapeño to the pot and sauté until softened and fragrant, about 4–5 minutes.
Return the beef to the pot, pour in enough Beef Broth to mostly cover the meat, add a Bay Leaf, bring to a simmer, cover and braise gently until the beef is fork-tender (1½–2 hours on the stove or 45–60 minutes in a pressure cooker).
Remove the beef and shred it with two forks; discard the bay leaf. Stir the shredded beef back into the braising liquid a few spoonfuls at a time to keep it moist and flavorful.
Mix the shredded beef with warm Refried Beans and shredded Chihuahua Cheese to create a cohesive filling—adjust salt and pepper to taste.
Warm the Flour Tortilla briefly in a dry skillet or microwave so they’re pliable, then place a generous scoop of filling near one edge, fold in the sides and roll tightly to form each chimichanga.
Heat a couple of inches of Neutral Oil in a deep skillet to about 350°F (175°C). Fry the chimichangas seam-side down in batches until golden and crisp, 2–4 minutes per side, turning carefully with tongs. Drain on paper towels.
Plate the chimichangas and top with shredded Lettuce, a drizzle of Mexican Crema, a dollop of Guacamole and spoonfuls of Salsa Roja. Finish with crumbled Queso Fresco and a squeeze of Lime.
Optional: for a lighter version, brush each filled tortilla with oil and bake at 425°F (220°C) on a parchment-lined sheet for 15–20 minutes, turning once, until crisp and browned.
