Preheat the oven to 400°F (200°C). Take out two baking sheets, one for the chickpeas, and one for the zucchini.
Chickpeas: Rinse the chickpeas, then pat them dry. Place them in a single layer on a parchment-lined baking sheet. Drizzle with olive oil and season with salt and garlic powder. Bake for 10 minutes on one of the upper racks while you prepare the zucchini.
Zucchini: Wash the baby zucchini and cut them lengthwise in half, then into 0.6-inch (1,5 cm) pieces. If using regular zucchini, cut them lengthwise in 4 before slicing. Place them on the other parchment-lined baking sheet. Drizzle with olive oil. Add salt and Italian seasoning. Bake for 25 minutes on a medium rack.
Quinoa: Rinse the quinoa. Add it to a saucepan with twice the volume of water and a pinch of salt. Bring to a boil. Then, reduce to medium heat and cook for 10-15 minutes until most of the water has been absorbed. Remove from the heat, cover with a lid, and let steam for another 10 minutes.
Cool down: Let the roasted zucchini and chickpeas cool down for 10-15 minutes or completely. Same for the quinoa or run it under cold water.
Dressing: Blend the olive oil, lemon juice, a whole quarter of a lemon with the pulp and the zest (seeds removed), garlic powder, and some salt until smooth.
Assembly: Add everything to a large salad bowl and toss with half of the dressing. Then, serve on individual plates and top with more dressing.