Warm the quinoa and chickpeas briefly: Place the 3/4 cup cooked quinoa and 1/2 cup cooked chickpeas in a microwave-safe bowl and heat for 30–45 seconds (or warm gently in a saucepan over low heat for 2–3 minutes). Warming them makes the quinoa fluffier and helps the chickpeas absorb the dressing so flavors meld instead of remaining 'cold' and separate.

If your roasted vegetables are fully cold from the fridge, reheat them for more flavor: Spread the 1 cup mixed roasted vegetables on a baking sheet and roast at 425°F (220°C) for 6–8 minutes, or warm them in a skillet over medium heat with a drizzle of olive oil for 3–4 minutes until edges caramelize. Re-warming concentrates their sweetness and revives the caramelized edges that give depth to the salad.

Make the dressing and bloom aromatics: In a small bowl whisk together 1 tbsp extra-virgin olive oil, 1 tbsp fresh lemon juice, the minced 1/2 clove garlic (if using), a pinch of Kosher salt and 1/8 tsp freshly ground black pepper. Whisking emulsifies the oil and lemon so each grain and veg gets an even coating; the salt helps release flavor from the garlic and binds the lemon into the oil.

Assemble base greens: Place a handful (about 1 packed cup) of baby spinach in a wide, shallow bowl. The spinach provides a fresh, slightly bitter counterpoint to the sweet roasted vegetables and gives the salad volume and color.

Combine grains, legumes and veggies: Add the warmed quinoa and chickpeas to the bowl with spinach, then top with the warmed roasted vegetables. Toss gently to distribute — using a folding motion preserves the lightness of the quinoa and avoids crushing chickpeas or wilting the spinach too much.

Dress and season: Pour the dressing evenly over the salad and toss again to coat. Taste and adjust: add a small pinch more salt or a squeeze more lemon if it tastes flat. Dressing right before serving prevents the salad from becoming soggy; tasting lets you balance acidity and salt.

Finish with feta and texture contrast: Scatter 2 tbsp crumbled feta over the top and give one last gentle toss so some feta melts slightly against the warm quinoa and chickpeas while some remains crumbly. The contrast of warm grains and cool, salty feta is key to the dish's charm.

Plate and serve: Transfer to a serving plate or bowl, add a final drizzle of olive oil (optional) and a grind of black pepper. Serve warm or at room temperature — the flavors deepen if it sits 10–15 minutes, making this an excellent make-ahead dish for a lunch or light dinner.