A fast and nontraditional approach, using a whole roasted chicken and slices of potatoes.
Make sure to spoon the tomato mixture over the chicken as you are serving it. If you use a larger chicken, add more ingredients. You can always double the potatoes, onions and tomatoes at anytime if you want more sauce. You can also quarter your potatoes and onions. I just happened to like them getting a little crispy as slices, and I prefer my onions sliced, because they caramelize in the juices.