Step 1 Heat the oven to 450 degrees. Meanwhile, in a large saucepan fitted with a lid, combine the rice and water and bring to a boil over high heat; reduce the heat and gently simmer until the rice is tender and the water is absorbed, 40 to 45 minutes.
Step 2 Meanwhile, brush the green onions lightly with olive oil and place directly on a stove-top burner. Cook, turning occasionally, until charred black on the outside and tender inside, 3 to 5 minutes. Chop the white parts of the green onions (save the greens for another use). You should have about 1/4 cup.
Step 3Line two baking sheets with aluminum foil. Slice the eggplants crosswise as thin as you can (use a mandoline if you have one). Toss with just enough olive oil to coat lightly, and sprinkle with 1/4 teaspoon each salt and pepper, or as desired. Arrange in a single layer on the baking sheet and roast, without turning, until browned and crisp, 7 to 10 minutes. Sprinkle lightly with lemon juice and salt and pepper to taste, cool on the pan, then remove to a bowl.
Step 4Toss the cauliflower florets with more olive oil, sumac, salt and pepper to lightly coat. Arrange in a single layer on a baking sheet lined with aluminum foil and roast until lightly browned, about 15 minutes. Sprinkle lightly with lemon juice and salt and pepper to taste and transfer to another bowl.
Step 5Slice the zucchini very thin lengthwise (use a mandoline if you have one). Heat 11/2 tablespoons olive oil in a skillet over high heat. When the oil is very hot, add the zucchini (it should sizzle immediately). Season with 1/4 teaspoon salt, or to taste, and sauté just until tender, about 3 minutes, tossing frequently to evenly cook the slices. Squeeze a little lemon juice over it and set aside.
Step 66. When the rice is cooked, add the green onions, yuzu juice, butter, sesame seeds, chopped peppers and 3/4 teaspoon salt, or as desired for vibrant flavor, to the rice and keep warm until ready to serve.
Step 7When ready to assemble, add 2 tablespoons olive oil, 2 tablespoons lemon juice and the sliced fresh herbs to the rice and toss gently. Taste and correct seasoning with more lemon, salt and pepper.
Step 8To serve, divide the tahini among the serving bowls, spreading it at the bottom of each bowl. Divide the rice, spooning it over the tahini in each bowl. Arrange some of the zucchini on a third of the surface of the rice in each bowl. Arrange the roasted cauliflower in a second third and the crispy eggplant on the remaining third of the rice surface. Top with spinach and sliced tomatoes, along with a sprinkling of Maldon salt, pepper and lemon juice. Serve immediately.