a metal pan...or lower the oven temperature 25 degrees.
Linda c

You're throwing away the best part! (Maybe not to you, but to me. LOL) They even have a pan that will give you more of the crunchy edges than the standard pan.

Here is a link that might be useful: Brownie Pan

More solutions to try.

Here is a link that might be useful: How to make brownie edges softer

Once upon a once there was the idea that if you wrapped the outside-side of the pan with a damp cloth it would temper the heat and the edges wouldn't get overdone. Some company even sold bands for just this purpose. Haven't seen any of this -- or the bands-- in years, but it might be worth the try.

I used to use westelle's idea on something I made. You can make the "bands" out of an old towel. Cut piece 3 in wide & long enough to go all the way around pan. So 9x12 pan would be 45 in. long,wet the strip but not dripping& double the piece over so it is 1 1/2 in wide all around & overlap & pin with safty pin Keep an eye on it after about 20 min. & don't bake at too high a temp.( about 350 ) don't let it touch sides of oven. It does keep some cakes from getting too crunchy on edges,so should work on brownies also. Might bake brownies 1 notch down in your oven maybe too close to top,could try that before you try the towel.Of course don't want to burn them on the bottom either! ~.~ Good luck!

Do you lower the heat 25 degrees like you're supposed to do with a glass pan? Ginger's tip site mentions something else that is often the reason they get over done. You need to not test in the middle but do test about an inch or so from the edge. If you try both of these and still have problems, you can turn the heat down another 25 degrees like Linda mentioned but you can also put the pan on a cookie sheet. It keeps the sides from getting the direct heat from below. Good luck.