cauliflower and divide into florets. In a large pot of boiling salted
water, cook florets until just tender, about 6 minutes. Drain and run
under cold water to stop the cooking.
Melt 1/2 tablespoon butter in a small saucepan over moderate heat.
Add bread crumbs and stir to coat with butter. Season with salt. Cook,
stirring, until bread crumbs are golden brown, about 5 minutes. Set
Melt 2 tablespoons butter in a small saucepan over moderate heat.
Add flour and whisk to blend. Cook 1 minute, then add milk, broth, bay
leaf and garlic. Bring to a boil, whisking, then adjust heat to
maintain a bare simmer and cook 8 to 10 minutes, scraping sides of pan
with a spatula occasionally. Season with salt and pepper. Remove bay
leaf and garlic. Keep warm.
Preheat oven to 400°F. Cut florets in half or quarters and arrange
in buttered low-sided oval baking dish just large enough to hold them
in one layer. Season with salt and pepper. Pour sauce over the
cauliflower. Tear prosciutto into shreds and scatter over sauce. Top
with cheese, then with bread crumbs. Bake in lower third of oven until
bubbly and browned, about 30 minutes. Let rest 15 minutes before
serving. Serve with chicken, lamb or pork.