Add all chicken ingredients to a large zip bag. Mix and let marinate for 20 minutes (can leave up to 12 hours).
Drain chicken, discard marinade.
Heat olive oil in a skillet over medium-high heat. Cook chicken until 165*F internally.
Remove chicken from pan and let cool.
Add all ingredients for cucumber salad to a large bowl. Mix, then set aside.
Mix all ingredients for the Tzatziki sauce in a medium bowl.
Divide rice, tomatoes, red onion, chicken, cucumber salad, and tzatziki sauce between meal prep containers.
No heating required, eat cold!