Here are a few TNT tips for you.
1) place a cookie sheet on a shelf a few inches below the brownie pan, it helps to even the heat.
2) when you cut the brownies, out of pan using a liner is best, experiment to see which you like best, foil or parchment, cut them on a bias. Cut the brownies lengthwise but on the cross cut start the cut a few inches off center. It will give your brownies a great look.
3) Grow your edible flowers from seed. Find a reputable organic dealer for seeds and plants and buy from them. One I have great luck with is www.groworganic.com