Cook quinoa as per package instructions undercooking by 4 minutes, see how to cook quinoa tutorial. Transfer to a large mixing bowl. Preheat oven to 375 F degrees and spray 9 x 13 baking dish with cooking spray. Set aside.
Preheat large non-stick skillet on medium heat and add ground turkey. Saute for 5 minutes, breaking into pieces with spatula while stirring. Transfer to the bowl with quinoa.
Return skillet to medium heat and swirl 1 tbsp of oil to coat. Add dried basil and thyme, saute for 30 seconds, stirring constantly. Add garlic and onion, saute until golden brown.
Add spinach in batches while stirring, and cook until it's wilted. Transfer to a bowl with quinoa and turkey, along with tomato sauce, bread crumbs, 2 cups of cheese, salt and ground pepper. Stir just enough to combine.
Transfer mixture into a baking dish, sprinkle with remaining 1 cup of cheese and bake uncovered for 25 minutes.
Cut into 8 pieces. Serve immediately garnished with tomatoes and green onions, no need to let casserole cool down.
Notes
Store: Refrigerate in an airtight container for up to 3 days.
Freeze: Up to 3 months.
Freezer meal: Assemble casserole. Tightly wrap the uncooked casserole with plastic, followed by foil, and freeze for up to 3 months. When you are ready to dig in, thaw in the fridge overnight and bake as per instructions + an extra 15 minutes. Remember to remove the plastic wrap prior to baking!
Make ahead: Assemble the casserole as per recipe instructions. Then just cover the uncooked casserole and refrigerate for up to 24 hours. It will still taste so fresh. Bake as per instructions.
Quinoa: Can be white or tri-colour. Red quinoa is too hearty and might be overpowering in a casserole.
Greens: Instead of spinach you can use chopped kale with ribs removed or swiss chard.
What are yellow and red veggies on top? They are finely diced tomatoes and bell pepper just for pretty photos. They are not necessary, just quinoa casserole is not the most appetizing looking dish but definitely delicious.
Other veggies: Diced sweet potato, brussels sprouts, bell pepper, broccoli or cauliflower would work instead of spinach as well.
Canned tomato products: If you don't have tomato sauce, diced tomatoes, passata or crushed tomatoes will work. Even pasta sauce will work, just use less salt then.
Cheese: Feel free to use a combination of different cheese you have on hand.