Slice cabbage into quarters; cut away the core, which is bitter. Peel and discard outer layers of cabbage until you get to the first unblemished layer of leaves. Break up the remaining layers of leaves and place in a bowl. Use a chopper to chop the cabbage by hand in the bowl, or chop on a flat work surface using a sharp knife. (Optional: Pulse cabbage in a food processor to a minced consistency.) Place minced cabbage back into the bowl.
Once cabbage is minced, add mustard, mayonnaise, salad dressing spread, and sugar. Toss well to combine. After several minutes, the cabbage will begin to release moisture. Cabbage is fully mixed when a spoon pressed down on the slaw yields pooled liquid. Serve.