To prepare the shawarma spiced potatoes, mix all the spices together in a small bowl until well incorporated. Set aside while you slice the potatoes. Slice the potatoes into ¼-inch slices and drizzle them with olive oil. Season the potatoes generously with the shawarma spice. Preheat oven to 375°F. Arrange the potatoes in an even layer on a silicon-lined baking sheet. Roast the potatoes for 20-25 minutes or until golden and crisp. The potatoes may need a flip in the oven about halfway through the cooking process. Keep warm until ready to serve.
To make the tahini dressing, combine the lemon juice, water, tahini, garlic, salt, and cayenne in a small bowl and stir until well combined.
To make the cucumber salad, place the halved cherry tomatoes in a medium bowl and toss with olive oil. Season with salt and pepper. Allow the tomatoes to marinate for about 5-10 minutes, then add the cucumbers and red onions and toss to combine. Right before serving, add the fresh herbs to the tomatoes and cucumbers.
To assembly the dish, arrange the potatoes in a nice layer in the serving bowl. Drizzle the potatoes with the tahini dressing and top them with the cucumber salad.
