You know how burgers shrink when you cook them? Instead of these perfect-round shaped patties that you crafted yourself, they become these awkward, small, patties. Where did the meat go!? Yeah, well they don't have to shrink.
To avoid your burger from shrinking, all you need to do is make a hole in the burger patty before setting it to cook.
When you create a hole in your burger, it will keep your burger flat while it's cooking. The hole doesn't need to be large -- it should be the size of a quarter. I am not sure of the science behind it, but it works!
Who's making me a burger?