Marinate the Chicken: In a bowl, mix Greek yogurt, olive oil, garlic, lemon juice, paprika, cumin, oregano, salt, and pepper. Add chicken and coat evenly. Marinate for at least 30 minutes or up to 8 hours.
Cook the Chicken: Heat a skillet or grill pan over medium-high heat. Cook chicken for 5–7 minutes per side until golden and fully cooked. Set aside.
Make the Tzatziki: In a bowl, combine Greek yogurt, grated cucumber, garlic, lemon juice, olive oil, dill, salt, and pepper. Mix well and chill until ready to serve.
Cook the Halloumi: In a pan over medium heat, sear halloumi slices for 1–2 minutes per side until golden brown.
Assemble the Bowls: Divide chicken, halloumi, cucumber, and optional potatoes among bowls. Add a generous scoop of tzatziki and serve with warm pita on the side.