Preheat the oven to 500°F (if using a baking sheet) or as high as it will go (if using a baking stone/steel; place the stone/steel in the oven before you start preheating).
In a colander in the sink, toss the sliced eggplant with the salt. Let sit for 10 to 20 minutes, then pat the slices dry with paper towels and set aside on a plate.
Stretch or roll out your dough to a 12-inch circle, then transfer it to an oiled baking sheet or a floured pizza peel (if using a baking stone/steel).
Brush the eggplant slices on both sides with a little oil and season generously with the za'atar spice blend.
Arrange the seasoned eggplant slices on the dough, and brush the edges of the dough with a little olive oil.
Transfer the pizza to the oven and bake until the crust is golden and the eggplant looks dry and has browned a bit, 8 to 10 minutes on the baking sheet, 6 to 8 minutes on the baking stone/steel.
While the pizza bakes, make the tahini sauce. Combine the tahini, garlic, lemon juice, salt, and cumin in a food processor. Process just until combined (about 30 seconds), then keep the motor running and stream in the ice water until the mixture lightens and the sauce becomes smooth and drizzly.
Take the pizza out of the oven. Drizzle with the tahini sauce and sprinkle with the fresh herbs. Slice and serve.