Pat the chicken breast dry and cut into small, even bite-sized cubes.
Heat the avocado oil in a large skillet or wok over medium-high heat.
Add the chicken cubes to the skillet, season with sea salt and black pepper, and cook until golden brown and cooked through, about 5-6 minutes. Remove the chicken from the pan and set aside.
In the same pan, add the toasted sesame oil, minced garlic, and grated ginger. Sauté for 30 seconds until fragrant.
Add the frozen peas and carrots along with the sliced bok choy. Stir-fry for 3-4 minutes until the vegetables are tender yet still crisp.
Push the vegetables to the outer edges of the pan and crack the egg into the center. Scramble the egg quickly until just set, then incorporate it into the vegetables.
Add the chilled cooked brown rice and the cooked chicken back into the pan.
Drizzle the coconut aminos over the mixture and toss everything together over high heat for 2-3 minutes, allowing the rice to get slightly toasted and everything to be well combined.
Garnish with thinly sliced green onions and serve hot.