Preheat oven to 375°F (190°C) and coat a 9x13 inch baking dish with non-stick cooking spray.
Place a large skillet over medium-high heat and brown the ground turkey with the diced onions and bell peppers until the meat is fully cooked and vegetables are softened.
Add minced garlic, salt, pepper, paprika, and oregano to the skillet; sauté for 1 minute until fragrant.
In a large mixing bowl, whisk together the liquid egg whites and blended cottage cheese until well combined.
Stir the cooked turkey mixture, cooked quinoa, and chopped spinach into the egg white mixture.
Pour the contents into the prepared baking dish and spread into an even layer.
Top the casserole with shredded mozzarella cheese.
Bake for 25 to 30 minutes, or until the egg mixture is set and the cheese is golden brown.
Remove from oven and let rest for 5 minutes before serving.