Stir in the macaroni and season to taste with Tabasco and salt. Pour the mixture into the prepared casserole.
If using the Parmesan, combine it with the bread crumbs in a small bowl. Sprinkle the bread crumb mixture (or the bread crumbs) over the macaroni. Bake for 15 minutes, or until the edges are bubbling and the top is golden. Serve hot.
Note: To lower the fat in this recipe, replace the half and half with 1 and 1/2 cups nonfat milk plus 1/4 cup nonfat yogurt and the cheeses with reduced fat cheese. When lowering fat in a cheese based recipe, you will often lose flavor, but flavor can be enhanced with the addition of finely chopped scallions.