Heat medium sauce pan over medium-high heat. Add 1 ½ teaspoons oil and coat pan. Add quinoa and cook for 2-3 minutes until lightly toasted, stirring frequently. Add water to pan and bring to a boil. Cover and reduce heat and simmer for 15 minutes or until water is absorbed.
Preheat oven to 400 degrees F. In a large skillet, add remaining tablespoon oil and sautée onions for 3-4 minutes until softened and golden. Stir in garlic during last minute of cooking. In a small bowl, whisk together milk and flour until flour is dissolved and then stir in chicken broth, salt and pepper. Add this broth mixture to skillet and bring to a boil, stirring constantly for 2 minutes until thickened. Remove skillet from heat and stir in 1 cup of cheese until melted.
Microwave cauliflower according to package directions. Carefully remove from bag and coarsely chop florets. Stir quinoa and cauliflower into cheese mixture. Place mixture into a 1 1/2 – 2 quart baking dish that has been lightly coated with cooking spray. Top with remaining cheese. Bake at 400 degrees F for 15-20 minutes or until heated through and cheese starts to bubble and brown. Garnish with chopped fresh Italian parsley.