Stir together the soy sauce, ginger, garlic, honey, and sesame oil in a small bowl.
Arrange the salmon fillets and bok choy halves in the slow cooker. Pour the sauce evenly over the top.
Cover and cook on low for 2 to 2.5 hours, until the salmon flakes easily with a fork.
While the salmon cooks, warm the cooked brown rice in a saucepan over low heat if needed, then stir in the sesame seeds.
Spoon the rice onto plates. Top each serving with one salmon fillet and bok choy halves. Finish with a sprinkle of sliced green onions.