Bake the sponge cakes until puffed and firm, about 12 minutes at 350°F. Transfer mixture to a piping bag and cut a small hole of the piping bag. Gradually add sugar will help greatly stabilize the meringue. google_ad_slot = "4156777732"; Beat egg white close to stiff peak –  The meringue should be whisked to a glossy and close to a firm peak. Add sugar in batches – Turn on high speed. Smoother top. Total Carbohydrate Start Replace tops. In a small saucepan, combine the flour, sugar, sugar substitute, salt and 2-1/2 cups milk until smooth. Slit them vertically but not completely. We are lightening the yolk mixture so that it will be of a more similar consistency to the meringue which will help you fold the meringue through easily and more evenly. The lady lock or cream horn filling recipe is what makes these cookies. The recipe only requires eggs, flour, and sugar.