In a bowl, combine lemon juice, lemon zest, olive oil, oregano, salt, and pepper. Marinate the chicken thighs in this mixture for at least 30 minutes.
Preheat a grill or skillet over medium heat. Cook the marinated chicken for about 5-7 minutes on each side, or until fully cooked. Remove from heat and let rest.
In a separate bowl, mix together Greek yogurt, chopped mint, minced garlic, salt, and pepper to create the Sizzled Mint Goddess Sauce.
Chop the cooked chicken into bite-sized pieces.
Assemble the bowls by placing the cooked rice or quinoa at the bottom, topped with cherry tomatoes, cucumber, red onion, chicken, and feta cheese.
Drizzle the Mint Goddess Sauce over the top, garnish with fresh mint leaves, and serve.