Slice the chicken breast into thin strips and place in a bowl with olive oil, cumin, coriander, turmeric, garlic powder, sea salt, and black pepper.
Toss the chicken until every piece is evenly coated in the spice mixture.
Heat a large non-stick skillet over medium-high heat and add the chicken strips in a single layer.
Sear the chicken for 6 to 8 minutes, turning occasionally, until golden brown on the outside and cooked through.
While the chicken is cooking, combine the diced cucumber, cherry tomatoes, and red onion in a small bowl to create a fresh salad.
In a separate small dish, whisk together the Greek yogurt, tahini, and lemon juice until the sauce is smooth and creamy.
Place the warm cooked brown rice in the base of a serving bowl.
Top the rice with the spiced chicken and the vegetable salad, then drizzle the tahini-yogurt sauce over the top before serving.