Pat the chicken breast dry with a paper towel and season both sides evenly with dried oregano, garlic powder, sea salt, and black pepper.
Heat the extra virgin olive oil in a medium skillet over medium-high heat.
Place the chicken in the skillet and cook for 6 to 7 minutes per side, or until the internal temperature reaches 165 degrees Fahrenheit and the exterior is golden brown.
Remove the chicken from the pan and let it rest for 3 minutes before slicing into bite-sized strips.
While the chicken rests, dice the cucumber and halve the cherry tomatoes.
Place the warm cooked brown rice in the base of a serving bowl.
Arrange the sliced chicken, cucumber, cherry tomatoes, and kalamata olives over the rice.
Sprinkle the crumbled feta cheese over the top and drizzle the entire bowl with fresh lemon juice before serving.