Slice the chicken breast into thin, even strips and place them in a bowl.
Toss the chicken with the dried oregano, garlic powder, ground cumin, sea salt, and black pepper until well coated.
Heat the olive oil in a non-stick skillet over medium-high heat.
Add the chicken to the skillet and sear for 5-7 minutes, turning occasionally, until the edges are crispy and the meat is cooked through.
While the chicken cooks, dice the cucumber and halve the cherry tomatoes.
In a small ramekin, whisk together the tahini and lemon juice, adding a teaspoon of warm water if needed to reach a drizzling consistency.
Assemble the bowl by placing the cooked quinoa at the bottom and topping it with the crispy chicken strips.
Arrange the cucumber and tomatoes alongside the chicken and drizzle the lemon-tahini sauce over everything before serving.