Preheat your oven to 375°F.
Cut the zucchinis in half lengthwise and scoop out the center using a spoon to create boats.
In a large bowl, combine the cooked quinoa, cherry tomatoes, feta cheese, olives, red onion, garlic, oregano, basil, salt, and pepper. Mix well.
Drizzle the olive oil over the zucchini boats and place them cut-side up on a baking sheet.
Fill each zucchini boat with the quinoa mixture, pressing down gently to pack it in.
Bake in the preheated oven for 25-30 minutes, or until the zucchinis are tender.
Remove from the oven and let cool for a few minutes. Garnish with fresh parsley before serving.