Start by toasting your shelled nuts for about 8 minutes at 350. This can vary so don't go far. You want them turning light brown and they should be fragrant. Let cool and roughly shop. Set aside.
Thinly slice the cabbage, radicchio, endive and fennel and place in a large bowl. Mix to combine.
Place Prosciutto on a cookie sheet and bake in the oven at 350 for 2-3 minutes. These don't take long to get crisp. They will look dried out, that's ok. when they cool they should easily crumble in your hands. If they don't they are still fine, just give a rough chop. Set Aside
Make your dressing by adding the vinegar, mustard and salt to a bowl, give a quick whisk. Slowly drizzle in your oils one at a time, whisking the entire time. It will thicken as you go. Funnel into a container when finished. If it separates after sitting, just give it a good shake before using.
To assemble we add the dressing to the cabbage first and give a good mix. We use our hands for this because you really want every piece to be coated. If you are doing smaller servings at a time (like we do throughout the week) just portion out the cabbage mixture into a smaller bowl and slowly add dressing until you reach the amount you like. You don't need much as it coats everything well.
Then we add the shaved Parmesan, we are generous per serving. We then add one slice of crumbled prosciutto on top and sprinkle with the roasted nuts.