Rinse the quinoa in a fine-mesh sieve under cold water until the water runs clear — this removes the natural saponins that can taste bitter. Drain well. Toast the dry, rinsed quinoa in a dry saucepan over medium heat for 2–3 minutes, stirring constantly until aromatic and slightly nutty. Toasting intensifies the grain's flavor and helps keep the cooked grains fluffy.

Add 2 cups (480 ml) water and 1/4 tsp salt to the toasted quinoa, bring to a gentle boil, then reduce to a simmer, cover and cook for 12–15 minutes until the water is absorbed. Remove from heat and let sit, covered, for 5–10 minutes to steam — this finishing steam relaxes the grain and yields tender, separate quinoa pearls. Fluff with a fork and spread on a rimmed tray to cool slightly so it doesn't wilt the other ingredients.

Prepare the eggplant: sprinkle the 1-inch cubes with 1/2 teaspoon kosher salt and place in a colander for 20 minutes. Salting draws out excess moisture and reduces any bitter edge, helping the eggplant caramelize rather than steam when roasted. After 20 minutes, rinse briefly and pat dry with paper towels to remove the excess salt and moisture.

Preheat your oven to 425°F (220°C). On a rimmed baking sheet toss the drained, salted eggplant cubes and the zucchini half-moons with 1 tablespoon of the olive oil and a pinch of black pepper. Roast on the middle rack for 20–25 minutes, turning once halfway through, until the vegetables are deeply golden at the edges and tender. High heat encourages caramelization, which concentrates sweetness and develops savory, roasted flavors.

While the vegetables roast, prepare the dressing: in a small bowl whisk together the tahini, lemon juice, minced garlic, remaining 1 tablespoon olive oil, 1/2 teaspoon kosher salt and 1/4 teaspoon freshly ground black pepper. Tahini can seize and become thick when acid is added — whisking briskly and adding small amounts of warm water (1–2 tbsp) will loosen it into a glossy, pourable emulsion. Taste and adjust salt or lemon if you want it brighter or creamier.

Heat the rinsed chickpeas in a skillet over medium heat for 4–5 minutes with a tiny splash of oil and a pinch of salt to warm through and remove any chill from the canning liquid; this also helps slightly dry the surface so they absorb dressing more readily. (Alternatively, use them cold if you prefer.)

Combine the cooled quinoa, roasted eggplant and zucchini, warmed chickpeas, and sliced roasted red pepper in a large mixing bowl. Toss gently to distribute ingredients evenly — you want to fold rather than mash the quinoa so the grains stay intact and fluffy.

Pour about two-thirds of the tahini-lemon dressing over the salad and toss, then taste. The reserved dressing lets you control how creamy and bright the salad is; add more as desired. The dressing's acidity will marry with the roasted vegetables and quinoa, brightening flavors while the tahini adds a silky, nutty counterpoint.

Finish with the chopped parsley and a final seasoning of salt and freshly ground black pepper. If you like, garnish with a drizzle of extra virgin olive oil, a sprinkle of lemon zest for brightness, or crushed red pepper for heat. Serve at room temperature or chilled — the salad keeps its texture well and the flavors meld in the fridge for a day.