In a medium saucepan, bring 2 cups of vegetable broth to a boil. Add 1 cup of rinsed quinoa, stir briefly, and reduce the heat to low. Cover and simmer for 12-15 minutes, or until liquid is absorbed.

In a large skillet, heat 1 tablespoon of olive oil over medium heat. Add 1 chopped onion and 2 minced garlic cloves, sautéing until fragrant.

Toss in 1 diced bell pepper, 1 chopped zucchini, and 1 cup of halved cherry tomatoes. Cook for an additional 5-7 minutes until vegetables soften.

Mix in 4 cups of baby spinach and cook until wilted.

In a large bowl, mix together 1 cup of tomato sauce and ½ cup of Greek yogurt until smooth. Add red pepper flakes if desired.

Incorporate the sautéed vegetables and cooked quinoa into the sauce mixture, stirring well.

Preheat your oven to 190°C (375°F). Grease a 9x13 baking dish with olive oil.

Pour the quinoa and vegetable mixture into the dish, spreading it evenly.

Sprinkle a layer of shredded mozzarella and grated parmesan on top. Cover with aluminum foil and bake for 20 minutes.

Remove the foil and bake for another 10 minutes, or until the top is bubbly and golden.

Let it cool for about 5 minutes before serving. Garnish with fresh parsley or basil.