First off, you can either nuke or bake your sweet potato. I nuked mine since it was much quicker.
Get out a mixing bowl and throw in your brown sugar, oil, and warm water. Take the cooked sweet potato, mash it up, and add to mixture. Mix that until it's a relatively smooth consistency (I don't own a mixer or anything to even mash the sweet potato, so I diced the sweet potato, and put all of it in the blender for maybe 10 seconds).
After that, add the remaining ingredients and mix/knead. There's a chance you might want to sprinkle a little more flour just to make it a little less sticky.
Put your dough into a greased loaf pan, cover with a towel, and let sit for 90 minutes in a dry warm area (on top of the stove perhaps).
Pop it in the oven set at 350 degrees Fahrenheit and let it bake for 30-35 minutes.
Take it out, cut yourself a slice while it's still hot, put a little Earth Balance and cinnamon on it, and you're in love!