Dice the chicken breast into bite-sized pieces and place them in a bowl.
Season the chicken with dried oregano, garlic powder, ground cumin, sea salt, and black pepper, tossing to coat evenly.
Heat the olive oil in a non-stick skillet over medium-high heat.
Add the chicken to the skillet and sear for 6-8 minutes, turning occasionally, until the edges are crispy and the meat is cooked through.
While the chicken cooks, prepare the dressing by whisking together the Greek yogurt, tahini, and half of the lemon juice in a small ramekin.
Assemble the bowl by placing the warm cooked quinoa at the bottom.
Top the quinoa with the crispy chicken, diced cucumber, halved cherry tomatoes, and finely diced red onion.
Drizzle the lemon-tahini sauce over the bowl and garnish with fresh chopped parsley and the remaining lemon juice.