Preheat oven to 450°F.

Place yogurt, mayo, water, and spices in a small bowl; whisk to combine the sauce and set aside.

Wash and dry the fresh produce.

Zest lemon into a medium bowl (reserve lemon for the dressing). Peel and mince garlic; add to the bowl along with oil and spices. Whisk to combine the marinade.

Pat chicken dry with paper towels, add to the bowl with the marinade, and turn to coat; set aside.

Place pita breads on a cutting board. Holding a knife parallel to the board, cut each pita in half horizontally to separate the two sides; cut or tear the bread into 1-inch pieces and place in another medium bowl.

Add oil, salt, and pepper to the bowl with the pita; toss with your hands to coat. Transfer to a baking sheet pan and spread out in an even layer. (Reserve bowl for later use.)

Place baking sheet in the oven (it doesn't have to be fully heated) and bake, tossing halfway through, until the pita chips are crisp, 5-6 minutes. Remove from oven.

Meanwhile, preheat a grill pan, outdoor grill, or skillet over medium-high heat.

Once the grill pan is hot, add chicken; grill until golden brown and cooked through, 3-4 minutes per side. Transfer to a plate.

While the chicken cooks, juice the lemon into the reserved bowl; add oil, Dijon, salt, and pepper. Whisk to combine the dressing.

Trim and small dice cucumber; halve tomatoes. Add both to the bowl with the dressing.

Shave parsley leaves off the stems; discard stems and mince the leaves. Add to the bowl.

Just before serving, chop or tear lettuce into bite-sized pieces; add to the bowl, along with pita chips, and gently toss to combine the salad.

To serve, divide salad and chicken between plates or bowls; drizzle chicken with sauce and enjoy!