Prepare Vinaigrette: Combine ingredients in small jar or container and shake until emulsifie. Set aside.
Assemble Salad: Heat the olive oil in large sauté pan over medium-high heat. Add the zucchini and sauté until golden brown on all sides. Season to taste with salt and pepper. Set aside to cool completely.
Once zucchini has cooled, place in a large salad bowl along with the cooked quinoa, halved cherry tomatoes, walnuts, cubed feta cheese, green onions, and lemon zest. Add the arugula leaves to the bowl and toss with vinaigrette (shake well before pouring). Season to taste with salt and pepper. Serve.