Combine eggyolks and condensed milk. Cook on top of a double boiler. Continuecooking until thick or of spreading consistency. Add the butter and vanilla. Blend well. Set aside.

Beat eggwhites and cream of tartar until it stands in peaks. Add the 1 cup of sugar gradually, beating continously. Flavor with vanilla. Spread meringue into a heavily oiled brown paper-lined cookie sheet.

Bake at 400°F for 20-22 minutes until brown. Loosen paper lining. While hot, spread the above filling. Roll as for jelly roll. Share and enjoy!