Read the Directions!
When I was in Bali, I took a cooking class. The first thing the chef said was read the recipe all the way through before you start. I thought to myself, that is such a basic request, I kind of laughed at the idea. Because, I have been cooking and baking and always scan through the recipe before I begin. After the goof of making brownies last week, I will ALWAYS read through the WHOLE recipe before beginning! Anther thing I will do is not assume things! Growing up when my mom would make brownies she would use a 8x8 pan, so I have been doing the same thing. So, when I made a recipe for brownies out of "Baked" I assumed that the recipe called for a 8x8 pan, but in fact in called for a 9x13 pan! That would explain the gooey middle that I discovered when I was trying to cut the brownies out of the pan and it was a complete mess I figured it out! But, the taste was so tasty that I ignored the gooey and still enjoyed the mess!