Preheat your oven to 375˚F.
Place the ham on a non-stick baking tray, or one lined with parchment paper or silpat. Add the tomatoes all around the ham. Bake in the oven for about 10 minutes or until the ham is crisp and the tomatoes have softened. Set aside.
Combine the first five dressing ingredients together in a small bowl. Slowly whisk in the vegetable oil until you have a dressing that has emulsified (is not separating). You can also do this in a jar and give it a good shake.
Assemble your salad: Place the washed and dried lettuce leaves in a large serving bowl. Top with the cubed avocado, roasted tomatoes and croutons. Roughly break the crispy ham on top of the salad. Sprinkle over the parmesan and snip some fresh chives on top. Serve drizzled with the dressing.
If your ham is thickly sliced you will require more cooking time in the oven. I like my ham really crispy so I use thin slices and bake them for 10 minutes.