Season chicken breasts with salt and pepper. Pour teriyaki sauce into slow cooker. Add chicken to slow cooker. Place diced onions and minced garlic on top of chicken. Drizzle toasted sesame seed oil over chicken. Set crockpot to HIGH and cook for 3 hours. While the chicken is cooking, prepare rice according to directions on the package. Cool to room temperature. When chicken is cooked, switch Crockpot to WARM function. Dice chicken into bite sized pieces. Then place diced chicken back into the slow cooker. Add rice, frozen peas and carrots, and soy sauce. Stir well to combine. Place lid on slow cooker. Lightly scramble and cook eggs in a skillet on the stovetop. Then add scrambled egg to rice mixture. Serve warm with green onions and sesame seeds.