An easy Mexican dinner for just 300 calories per serving. You can even assemble it ahead of time, refrigerate, then bake just before serving!
You can prepare the casserole up to a day ahead; cover and refrigerate. Bake as directed, adding about 5 minutes to bake time to compensate for the refrigeration.
You can serve with tortilla chips for topping or dipping into the casserole; however, it will add more calories.