• Preheat the oven to 275°F
• Sprinkle both sides of the chuck roast with the salt and pepper. Heat some cooking oil in a large oven-proof pot over medium heat. When the oil is hot, brown the roast for 2 to 3 minutes on each side. Set the roast aside on a plate.
• Add the wine to the pot and scrape the brown bits off the bottom of the pot. Place the browned roast back in the pot. Add enough beef stock to cover the meat halfway. Toss in the bay leaves and oregano. Put the lid on the pot and transfer to the middle rack of the oven. Roast for 6 to 7 hours, or longer, to the point the meat is so tender it falls apart when pierced with a fork.
• Remove the pot from the oven and transfer the beef to a plate. Reserve one cup of the cooking liquid in the pot.
• Shred the meat with two forks. It will shred easily while it is still warm. Place the shredded beef in a covered bowl while you prepare the filling.
• Heat the oil in a large skillet, add the onions and cook until they are translucent, add the garlic and cook an additional one minute. Remove the skillet from the heat and add the green peppers, oregano, cumin, and chili powder. Transfer the filling to the reserved bowl of shredded beef.
• Add the butter to the same skillet over medium-high heat and when it has melted add the flour, cook and stir for two minutes, then add the reserved roast beef liquid, whisking and cooking to a smooth sauce. Remove from heat and allow to cool slightly, then add to the bowl with the shredded beef mixture and combine thoroughly.

To Assemble the Chimichangas:

• Preheat the oven to 425°F
• Line a baking sheet with parchment paper and oil or spray with non-stick cooking spray.
• Working with one tortilla at a time, place about 3/4 cup of the meat mixture in the center of the tortilla. Add 2 or 3 tablespoons of the cheese. Fold the ends inwards and roll the tortilla up. Place seam side down on a parchment-lined baking sheet. Continue with the remaining tortillas.
• Brush oil over each chimichanga and place the baking sheet in the preheated oven. Bake for 15-20 minutes, or until golden brown. Sprinkle a bit more cheese over the top of the chimichangas and bake for 2 minutes to melt the cheese on the top.
• Serve with additional cheese and provide condiments of salsa, avocado slices and sour cream.