Take two-thirds of the butter and allow it to soften, then mix in the mustard, hot pepper sauce, or cayenne pepper, Worcestershire and salt and pepper. Rub this mixture thoroughly over the spatchocked poussins. Lay them in a large oven dish and cover with the bread pieces. Dot the remaining butter over the bread pieces.
Roast in a preheated 350 degree oven at for 40 minutes. If the bread pieces start to burn, cover the dish with foil.