Slice the chicken breast into thin, bite-sized strips.
In a small bowl, whisk together the cumin, coriander, turmeric, garlic powder, sea salt, and black pepper.
Toss the chicken strips in the spice blend until evenly coated.
Heat the olive oil in a non-stick skillet over medium-high heat. Add the chicken and sauté for 6-8 minutes until golden brown and cooked through.
While the chicken cooks, dice the cucumber, halve the cherry tomatoes, and finely mince the red onion.
In a small ramekin, stir together the Greek yogurt, lemon juice, and dried oregano to create the sauce.
Place the warm cooked brown rice in the center of a bowl.
Arrange the spiced chicken, diced cucumber, tomatoes, and red onion over the rice.
Top with the lemon-yogurt sauce and serve immediately.