Slow Cooker

1. Add the beef broth, soy sauce, rice vinegar, onion, garlic, ground ginger, salt, and red pepper flakes to the slow cooker.
2. Season the chuck roast on all sides with salt and black pepper.
3. Heat the oil in a large skillet over medium-high heat. When the oil is hot, add the chuck roast and sear it for 3 to 4 minutes per side, until a brown crust forms. Transfer the seared roast to the slow cooker.
4. Cover and cook on on HIGH for 4 to 5 hours or LOW 8 to 10 hours, or until the beef is tender and shreds easily with a fork.
5. Remove the chuck roast from the slow cooker. Shred the meat and discard any large pieces of fat.
6. Turn the slow cooker to HIGH if not already on the setting. Stir in the frozen stir-fry vegetables, the uncooked ramen noodles, and the shredded beef.
7. Cover and cook on HIGH for 5 to 10 minutes, gently stirring once halfway through, until the ramen is tender. Cooking time will vary depending on the brand of noodles and the heat of your slow cooker.
8. Stir everything together and turn off the slow cooker. Let the beef ramen rest uncovered for 5 to 10 minutes so the noodles can absorb more of the sauce.

Instant Pot

1. Cut the chuck roast into three or four large pieces. Pat the pieces dry and season them on all sides with salt and black pepper.
2. Turn on the Instant Pot and select Sauté. Once hot, add the oil. Working in batches if necessary, add the beef and sear it for 2 to 3 minutes per side. Remove the browned beef and set it aside.
3. Pour the beef broth into the pot. Use a wooden spoon to scrape up any browned bits from the bottom so the Instant Pot does not display a burn warning.
4. Add the onion, garlic, soy sauce, rice vinegar, ginger, salt, and red pepper flakes. Stir to combine, then return the seared beef to the pot.
5. Close and seal the lid. Cook on HIGH pressure for 60 minutes. When the cooking time is complete, allow the pressure to release naturally for 15 minutes, then carefully release any remaining pressure.
6. Remove the beef and shred it, discarding any large pieces of fat. Skim excess fat from the cooking liquid if needed.
7. Select sauté and add the frozen stir-fry vegetables. Cook for 2 to 4 minutes, stirring occasionally, until the vegetables are heated through.
8. Return the shredded beef to the pot. Add the uncooked ramen noodles and press them into the liquid. Cook on sauté for 3 to 5 minutes, stirring frequently, until the noodles are tender. Turn off the Instant Pot as soon as the ramen is cooked to prevent it from becoming mushy.
9. Let the dish rest for 5 minutes before serving. The noodles will continue to absorb the sauce as they stand.