Marinate Chicken: Whisk together olive oil, lemon juice, minced garlic, paprika, cumin, salt, and pepper. Add chicken and marinate for at least 30 minutes.

Cook Chicken: Heat grill or skillet, cook chicken for 6-8 minutes per side until golden brown and internal temperature reaches 165°F. Let rest before slicing.

Prepare Vegetables: Wash and dice cucumber, tomatoes, red onion, and bell peppers into bite-sized pieces. Mix well in a bowl.

Make Tzatziki: Combine Greek yogurt, grated cucumber, minced garlic, and lemon juice, seasoning with salt. Mix well and set aside.

Assemble Bowls: Layer vegetables in serving bowls, top with sliced chicken and dollops of tzatziki sauce. Serve with warm pita bread.