01 - In a mixing bowl, combine olive oil, lemon juice, minced garlic, oregano, thyme, paprika, salt, and black pepper. Add the chicken breasts and coat evenly. Cover and refrigerate for at least 20 minutes or up to 2 hours for deeper flavor.
02 - Heat olive oil in a saucepan over medium heat. Add the rice and stir for 1 minute to toast slightly. Pour in water and salt, bring to a boil, then cover, reduce heat to low, and simmer for 12 to 15 minutes. Remove from heat and let rest, covered, for 5 minutes. Fluff with a fork.
03 - Grate the cucumber and squeeze out excess moisture using a clean towel. In a bowl, combine Greek yogurt, the grated cucumber, chopped dill, minced garlic, olive oil, lemon juice, salt, and pepper. Stir until smooth and refrigerate until ready to serve.
04 - Heat a grill pan or skillet over medium-high heat. Remove the chicken from the marinade and grill for 5 to 6 minutes per side until fully cooked through and golden. Transfer to a cutting board and rest for 5 minutes before slicing against the grain.
05 - Divide the fluffed rice among four bowls. Arrange sliced grilled chicken, diced cucumber, halved cherry tomatoes, sliced red onion, Kalamata olives, and crumbled feta over each portion. Spoon tzatziki generously on top and finish with fresh parsley or dill and lemon wedges.