First, make the dressing. Grind the salt and pepper into a screw-top jar, add the sugar and mustard, 1 tbsp of oil, close and shake well. Repeat with each tbsp of oil until you have an emulsion. Chill until neede
Remove the outer leaves from the endive, discard, and then brush the outsides of each with a thin layer of lemon. Peel the pears and brush with lemon too. You need to work quickly now as the endive and pear have a tendency to discolour fairly rapidly. Chop off the woody end, removing the bitter core, and slice each endive down the long middle. Slice half diagonally into thin juliennes, and the other half lengthways into slightly thicker strips. Put the former into a mixing bowl, and the latter onto your plates/bowls as a base for the salad.
Slice up ¾ of your pears into small-to-bite-size chunks and put these into the bowl. Slice the remainder into thin julienne and reserve for garnish.
Add most of the walnuts, and crumble in most of the cheese, and then toss with enough dressing to bring everything together. Don't feel you have to use all of the dressing, as you need to make sure it doesn't end up greasy.
Distribute this mix over the pre-laid bases evenly (unless you're feeding little ones, of course; in which case, act accordingly) and top with some more walnuts, pear chunks, and a little more crumbled cheese. Drape ¼ of the julienne pear on the top of each, along with a slice of the ham (if using). Drizzle over a little more dressing or some oil and scatter over the chives (if using).
Serve!
