Rinse the rice under cold water until the water runs clear. Combine the rice and water in a rice cooker and cook according to the manufacturer's instructions.

In a mixing bowl, combine the ground beef, soy sauce, brown sugar, sesame oil, garlic, and ginger. Mix well and let marinate for 10 minutes.

Heat a skillet over medium-high heat. Add the marinated beef and cook until browned and cooked through, about 5-7 minutes.

In the same skillet, add the broccoli, carrots, and bell pepper. Stir-fry for about 5 minutes until the vegetables are tender-crisp.

Serve the cooked beef over a bed of rice and top with stir-fried vegetables. Garnish with chopped green onions.