Combine the mashed potatoes, eggs, ¾ cup of the cheese, chives and ham in a mixing bowl. Mix well. Season with salt and pepper, if desired.
Spray a muffin tin with nonstick cooking spray. Fill the tins with the mashed potato mixture. Top with the remaining cheese.
Bake in a preheated 400-degree F oven until tops are lightly browned, about 20 minutes.
