If using fresh broccoli, steam the florets in boiling water for about 2-3 minutes until slightly tender, then drain. For frozen, simply microwave according to package instructions until just thawed.
In a large mixing bowl, combine the shredded chicken, steamed broccoli, cooked quinoa, cheddar cheese, cream of mushroom soup, Greek yogurt, garlic powder, onion powder, black pepper, salt, and paprika. Stir until all ingredients are evenly incorporated.
Lightly grease a 9x13 inch casserole dish with olive oil. Pour the mixture from the bowl into the casserole dish, spreading it out evenly.
If you like a crunchy topping, mix breadcrumbs with a bit of olive oil and sprinkle it evenly over the top of the casserole.
Place the casserole in the preheated oven and bake for 25-30 minutes, or until the cheese is bubbly and golden brown.
Once done baking, let the casserole cool for 5 minutes before serving. Enjoy it warm!