In a food processor, shred the bread and Parmesan Cheese together until it becomes crumb like.
In a large saucepan, melt butter over medium low heat and add flour. Cook whisking vigorously for 2 minutes, being very careful not to burn. Add milk. Cook for another 2 minutes.
Increase heat to medium-high and add cauliflower. Bring to a boil, then reduce to a simmer. Cover pot and cook for abut 5 minutes until the cauliflower begins to soften. Add ham and remaining cheese. Remove from heat. Season with salt and pepper to your liking.
Cool mixture and scoop spoonfuls of the mixture into a muffin tin with each cup coated with non stick cooking spray. Cover the top of each "muffin" with the bread and Parmesan mixture.
Bake in a 350 degree oven for about 20 minutes, covered with foil. Remove foil and bake for about another 15 minutes, until bubbly and golden brown on top.