01 - Combine olive oil, lemon juice, minced garlic, dried oregano, smoked paprika, salt, and pepper in a bowl. Add chicken breasts and coat thoroughly. Allow to marinate for at least 20 minutes.
02 - Place torn kale leaves in a large bowl. Drizzle with olive oil, lemon juice, and a pinch of salt. Massage kale with hands until leaves become slightly softened and turn bright green, approximately 1 minute.
03 - Halve cherry tomatoes, dice cucumber, and thinly slice red onion. Slice avocado immediately before serving to prevent browning.
04 - Whisk Greek yogurt, olive oil, lemon juice, honey, Dijon mustard, salt, and pepper in a small bowl until fully combined and smooth.
05 - Heat grill pan or skillet over medium-high. Grill marinated chicken for 6-7 minutes per side until fully cooked. Remove from heat and let rest for 5 minutes before slicing against the grain.
06 - Divide massaged kale evenly among 4 bowls. Top with sliced grilled chicken, cherry tomatoes, cucumber, red onion, avocado slices, and crumbled feta if desired.
07 - Drizzle dressing generously over each bowl and serve immediately while chicken is warm.