How to keep the burgers flat

If you add egg and breadcrumbs, you aren't cooking a burger, you're cooking meatloaf.

Try using just good beef with plenty of fat (80% meat, 20% fat is the ideal ratio, lean mince is not good for burgers), and pepper. Get the pan good and hot, salt the burgers well (don't add salt beforehand), brush the burgers with oil, then whack them on the pan, 5-6 minutes a side (depends on thickness) and you'll get a nice brown crust.

A couple of other tips: make the burgers plenty ahead of time so they can sit in the fridge for a good few hours. And never press the burger down with your spatula, you just end up losing all the juiciness.

Check out The Burger Lab's Top Ten Tips for a Better Burger for more tips.

It strikes me that it would be a bit overpowering, and that even with a binder you would have a hard time keeping it together. Cured ground beef just seems like it would be nasty :-)

I've experimented myself with two 'inclusions' in fresh beef patties. One is bacon (cooked), the other is salami. They are both interesting, and if minced finely and added to the grind they do not interfere with texture but add some excellent flavors and saltiness.

I would imagine pastrami would give you a nice result as an inclusion too. I'd chop it up and mix it in with the cubed up beef before you run it through the grinder.

With burgers really the fresher the better. I grind about 2 hours before grill time, and that is only so I can throw the patties into the freezer. I like them thin and cooked through, so I need to freeze them so they hold their shape better during the first side cooking. If you like your burgers to have some pink you'll probably want to skip the freezer.