Fill any unused cups halfway with water to prevent over browning of the muffins or warping of the pan. (joyofbaking.com)
(After 50 minutes you can tent the loaf with aluminum foil to prevent over browning on top.) (healthyflour.com)
Cover them with foil just like you would a regular pie crust to prevent over browning and knock your oven temp back 25 degrees. (homeiswheretheboatis.net)