Erin Chase, AKA $5 Dinner Mom has written a number of books and a blog about dinners that consist of ingredients of under $5.
Tonight I made Southwest Macaroni and Cheese and plan on trying the Spicy Quinoa later in the week. With the many recipes available,you can make homemade mac and cheese and other casseroles or hotdishes as quick and easy as the boxed ones you can purchase. By making your own you know what ingredients are in them and may be able to avoid some of the unknown ingredients that in the boxed meals.
It is also a way to use up leftovers you may have. It is also an easy way to make a hearty meal with inexpensive items such as beans and vegetables.
While I was putting this together, I also made a batch of Copy Cat Eggo Waffles with mini chocolate chips to put in the freezer. Again, along with saving money, you know what ingredients are in them.