Brown the beef: Heat a skillet over medium-high. Cook ground beef until browned and crumbled, about 5-7 minutes. Drain excess fat if needed. This step builds rich flavor. Layer the slow cooker: Add browned beef, carrots, bell pepper, green onions, garlic, and ginger to a 6-quart slow cooker. Mix the sauce: In a bowl, whisk soy sauce, brown sugar, broth, rice vinegar, and sesame oil until sugar dissolves. Pour over beef and veggies. Stir gently. Slow cook: Cover and cook on low for 4-6 hours, until veggies are tender but crisp. Add noodles: Increase to high. Add ramen noodles, pressing down to submerge. Cook 20-25 minutes until al dente. Stir halfway to prevent sticking. Serve: Ladle into bowls. Garnish with sriracha, sesame seeds, egg, and extra green onions. Enjoy hot!