Toss the cauliflower florets and eggplant slices with a bit of vegetable oil. Arrange them on separate baking sheets in a single layer. Roast in the preheated oven for about 20-25 minutes, or until they are golden brown and tender. You may want to flip them halfway through the cooking time. Once done, remove from the oven and set them aside to cool slightly.
While the vegetables are roasting, prepare the quinoa. Rinse 1 cup of uncooked quinoa under cold water. In a medium saucepan, combine the rinsed quinoa and 2 cups of water. Bring it to a boil over medium-high heat. Once it boils, reduce the heat to low, cover the saucepan, and let it simmer for about 15-20 minutes, or until all the water is absorbed and the quinoa is fluffy. Remove it from the heat and let it sit, covered, for about 5 minutes. Fluff the cooked quinoa with a fork.
To make the tahini sauce, combine the tahini paste and lemon juice in a small bowl. Slowly add the water while whisking until the sauce has a light, creamy consistency. Season with sea salt, freshly ground black pepper, and chilli powder (if using).
For the coriander salsa, mix together the olive oil, lemon juice, minced garlic, fresh coriander, red chilli, salt, and a pinch of black pepper. Set it aside.
Serve family style in a large platter or in individual portions in a bowl., Start by layering with a bed of rocket leaves on the plate.Top with the cooked quinoa, roasted cauliflower florets, and eggplant slices.
Drizzle the tahini sauce generously over the roasted vegetables and finish by spooning the coriander salsa on top. Keep extra coriander salsa and Tahini sauce on the side.