To prepare the zucchini, cut each zucchini lengthwise into 4 slices about ¼ inch wide. Place the zucchini in a single layer on a baking sheet. Coat on both sides with the olive oil and Preserved Lemon BBQ Sauce, then sprinkle with the salt.
Prepare a hot fire in a grill, or preheat a grill pan on the stovetop over high heat. Spray the grill grates or grill pan with cooking oil spray. Place the zucchini on the grill or grill pan and cook, turning once and brushing with more Preserved Lemon BBQ Sauce throughout the cooking, until nicely grill-marked and tender, about 3 minutes per side. Transfer to a plate.
To prepare the herb salsa, in a small bowl, stir together the parsley, scallions, olive oil and Preserved Lemon BBQ Sauce. Taste and adjust the seasoning with BBQ sauce and salt.
To prepare the tahini, in a medium bowl, whisk together the tahini paste, water, Preserved Lemon BBQ Sauce, turmeric (if using) and salt until fully combined. Taste and adjust the seasoning with BBQ sauce and salt.
To assemble, spread the tahini on a serving plate and arrange the zucchini on the tahini. Top with the herb salsa and sprinkle with the pine nuts and cheese (if using).