Heat the oil in a large skillet over medium-high heat for just a minute or two.
Coat the chicken with the za’atar and salt.
Lay the chicken in the hot skillet, ensuring that the pieces aren’t too close together. Cook them on one side without flipping for 5 to 7 minutes, or until some nice, golden brown color starts to form.
Flip them over and cook another 5 to 7 minutes. If the internal temperature isn’t registering 165ºF (74ºC) at this point, transfer the whole skillet to the oven and finish cooking the chicken, 5 to 10 minutes.
Set aside the chicken once it’s done and allow it to rest for 5 to 10 minutes, and then slice it thinly and drizzle with the pomegranate molasses.
To assemble the sandwiches, lay out the bread and divide the pomegranate seeds evenly over 4 slices.
Top each with ¼ cup (30 g) of the cucumbers. Divide the chicken slices among the sandwiches, top with the arugula and remaining bread slices.