You'll need a food processor for this. If you don't have one you can try your best to finely mince the cauliflower, walnuts, and other ingredients. Depending on the size of your food processor you may have to do this in batches to successfully chop everything. If so, stir it all together in a large mixing bowl before baking. It's summer now so I like to prepare the cauliflower walnut taco meat in my toaster oven to avoid heating up the whole kitchen. If you don't have one, you can do it in the regular oven or sauté the taco meat in a skillet for about 30 minutes, stirring regularly. When making in my small toaster oven I must bake it in batches.