Brine chicken breasts in 4 cups cold water mixed with 1 tablespoon kosher salt for 15-30 minutes.
Meanwhile, rinse rice and quinoa in cold water. Preheat oven to 425°F (220°C).
Chop all vegetables into uniform 1-inch pieces to ensure even cooking. Dice sweet potato into ½-inch cubes.
Pat chicken dry after brining, then season with garlic powder, paprika, and black pepper.
Start brown rice: Combine 2 cups rice with 4 cups water. Bring to boil, reduce to simmer, cover and cook 35-40 minutes.
Simultaneously, prepare quinoa: 1 cup quinoa with 2 cups water, simmer covered for 15-20 minutes.
Arrange chicken breasts on one half of a sheet pan, drizzled with 1 tablespoon olive oil. On the other half, arrange sweet potato cubes tossed with remaining olive oil.
Bake chicken and sweet potatoes for 22-25 minutes until chicken reaches 165°F internal temperature and sweet potatoes are fork-tender.
In batches, sauté vegetables in a large skillet over medium-high heat: onions first (3-4 minutes), followed by bell peppers, zucchini, and yellow squash (4-5 minutes), and finally quick-cooking vegetables like broccoli (3 minutes) and spinach (1 minute until wilted).
Allow chicken to rest for 5 minutes, then slice into ½-inch strips against the grain.
Prepare sauce combinations and store in separate containers: Teriyaki (soy sauce, honey, rice vinegar), Lemon-Tahini (tahini, lemon juice, water), Balsamic (balsamic, olive oil, honey), Sesame-Ginger (sesame oil, vinegar, soy sauce), and Cilantro-Lime (lime juice, oil, cilantro).
Portion components into meal prep containers according to the variation chart in the recipe. Keep sauces separate until ready to consume.
Cool completely before refrigerating. Store in refrigerator at 36-38°F for up to 5 days.