Preheat oven to 350 degrees.
Pour the remaining 1/2 cup brown sugar into a separate medium sized bowl. You can start with about 1/4 cup and add more as you go. Coat the tomatoes in the sugar on both sides. Lay the tomato slices on the same wire rack over the baking sheet you are using/used for the bacon in a single layer.
Roast the tomatoes for about 30 - 45 minutes, then turn the tomatoes over. Continue to cook for about 15 minutes more. You want the tomatoes to start to caramelize and turn an amber color.