Browning meat for me, whether it be chicken or beef, can be a hit or miss for me, and pretty much at the end of it all I have no idea what I did right or wrong.
There are a few basic rules and if you've got the same problem I do when it comes to browning meat then I'm pretty sure you and I both know only but a couple of these basic rules.
I'm sure we all know this one, RULE #1 Don't use a non-stick pan. The point is to use a pan that will allow the meat drippings to stick creating browning affect.
RULE #2 Don't use a fork to flip the meat. This punctures the meat allowing the meat juice to escape, this will only dry out your meat in the end.
RULE #3 Take the time to preheat your pan. Preheat your pan thoroughly on low, add the butter, oil or both and then turn up the heat before adding the meat. If the pan is too hot before adding the fat (butter, oil or etc.) the fat will just end up burning.
RULE #4 Dry your meat. Whatever you do, dry your meat with a paper towel before browning to achieve less oil spits and a nicer brown.
RULE#5 Don't crowd the pan! I'm sure you've heard this one before. A jumble of meat in a pan all piled together will only create a steaming affect. When the juices from the drippings can't find a way to escape (a.k.a. evaporate) there will be no browning only steaming. Brown in batches if you have to, and most likely you'll always have to, unless you're cooking for one or two.
RULE #6 Leave the meat alone! Yes, I know this is hard. But allow the meat to brown thoroughly on each side without interruption. If you find that the meat has stuck to the plate leave the meat alone until it comes off the pan readily.
So those are the basic rules. If you want to know more detailed information all about browning (and I mean everything there is to know about browning) check out this site on browning, how to brown meat @ missvickie, it's loaded with information on the subject, if anything it'll be really interesting.