Cook brown rice according to package directions (something along the lines of bring the rice to a boil in a covered saucepan. Reduce heat to low and simmer for 40-50 minutes until all the water has been absorbed).
Heat a large skillet over high heat. Add in the olive oil, let heat for about 30 seconds, and add in the onion, baby bok choy, carrots, peas, and mushrooms. Let cook over the high heat until the vegetables reach desired doneness (5-7 minutes).
Add in the cooked rice and season with soy sauce and sesame oil. Serve.