Slice the chicken breast into thin, bite-sized strips and place them in a medium mixing bowl.
Toss the chicken strips with the sea salt, black pepper, dried oregano, garlic powder, and cumin until every piece is thoroughly coated.
Heat the olive oil in a large non-stick skillet over medium-high heat until shimmering.
Add the seasoned chicken to the skillet and sauté for 6-8 minutes, turning occasionally, until the edges are golden-brown and crispy.
While the chicken cooks, dice the cucumber into small cubes and halve the cherry tomatoes.
In a small bowl, whisk together the non-fat Greek yogurt and lemon juice until smooth to create the dressing.
Assemble the bowl by placing the warm cooked quinoa at the base, then top with the crispy shawarma chicken and the fresh vegetable salad.
Drizzle the lemon-yogurt sauce over the entire bowl and serve immediately while the chicken is hot.