Skip the Bun - Skip the Crust
For many, the bun and the crust are the best part. But you can eliminate a large amount of fat and calories by not using them. They are often just the delivery system for the good part - the filling. If you are a big bun/crust lover, consider having them by themselves as a treat.
Burgers like Sloppy Joes and other seasoned patties are a great example for skipping the bun. Just put the Sloppy Joe mix on the plate and add a side of veggies, or even oven baked fries. Seasoned patties work well because you are usually putting other fixings on top, so do that on the plate and maybe add more of them, or a side of veggies to round it off. Less calories, more nutrition - which leaves room for more dessert!
Pie crust is not necessary for all pies. I have made cheesecakes and pumpkin pies without a crust with great results. Coconut oil is an excellent non-stick coating, and you get the added health benefits too.