Woman's Institute of Domestic Arts and Sciences, Woman's Institute Library of Cookery…
“ Cook the sugar and water until it threads. Beat the eggs and add the sirup to the beaten eggs. Then add the thin cream, return to the fire, and cook until the mixture thickens. Set aside to cool. Beat the heavy cream until it is stiff, and fold this into the custard. Make macaroon crumbs by drying macaroons and beating them until they are quite fine. Add 1 cupful of these crumbs and the vanilla to the parfait mixture, place in a mold and freeze. When frozen, remove from the mold, pack in paper cases, cover with a layer of macaroon crumbs, and serve. ”
