Dice the chicken breast into bite-sized pieces and season evenly with sea salt and black pepper.
Heat the sesame oil in a large skillet or wok over medium-high heat until shimmering.
Add the chicken to the pan and sauté until golden brown and cooked through, about 5-6 minutes, then remove and set aside.
In the same pan, add the diced white onion, minced garlic, and grated fresh ginger, sautéing until fragrant and translucent.
Stir in the frozen peas and carrots, cooking for 3-4 minutes until they are tender and heated through.
Push the vegetables to the outer edges of the pan and crack the egg into the center, scrambling it until fully set.
Add the cooked jasmine rice and the cooked chicken back into the pan, drizzling the tamari over the top.
Toss all ingredients together for 2-3 minutes until the rice is slightly toasted and everything is well combined.
Remove from heat and garnish with thinly sliced green onions before serving.