arcgis desktop - Cutting Polygon in Two in ArcMap?

For ArcMap10: I know there are multiple way to do this, but I wanted to see what was the most efficient for this case, as I will be doing it repeatedly in my workflow. I have a .shp polygon layer with multiple polygons within it. I need to change one polygon within this, and am simply dividing it into two pieces. They are property tracts, and one owner has sold half of his portion, now making it two separate tracts. So, the property tract is currently 1028, and needs to become 1028 and 1028A. I have thought of simply deleting, and re-drawing, but is there a more efficient way?