Any kind of sausage plus some herbs or spices and cheese is a great addition to a quinoa/onion base. I do Italian sausage/parsley/parmesan, chorizo/cilantro/queso fresco, or merguez/carrots/cumin. I brown the sausage, then sautee the veggies and spices, fold in the cooked quinoa and herbs, then stuff and bake with cheese/breadcrumbs on top.