Make Tahini Dressing: In a small bowl, whisk together the tahini, lemon juice, salt, and pepper to make the dressing. Add water, a little at a time, until the dressing reaches your desired consistency.

Prepare Pita Bread: Cut the pita bread in half to form pockets. If desired, you can warm the pita bread slightly in a toaster oven or dry skillet.

Spread Hummus: Spread a generous layer of hummus inside each pita pocket.

Fill with Vegetables: Fill the pita pockets with the sliced cucumber, sliced tomato, thinly sliced red onion, and shredded lettuce.

Drizzle with Dressing: Drizzle the tahini dressing over the vegetables inside the pita pockets.

Serve: Serve immediately.