Southwestern quinoa casserole from Pinch of Yum is a quick and easy gluten-free meal. Spiced quinoa is layered with charred peppers and black beans before being topped with plenty of cheese and chopped green onions. You should be able to find quinoa at your local grocery store or health foods store. There are several varieties of quinoa including black, red, and white quinoa. Any one will work for this recipe. For full recipe instructions, click here.