Put into a copper basin half a pound of powdered sugar. Break in seven whole eggs, and grate in the rind of half a lemon. Beat well together with the wire-whip for one minute; then place it on a slow fire and heat it slightly, stirring it sharply and continually. Take it from the fire, and beat it well until thoroughly cold. Remove the whip and with a skimmer mix in carefully and slowly half a pound of well-sifted flour; two minutes and a half will be sufficient. Butter the interior of a one-quart, round cake-mold, and line it with paper, keeping it an inch and a half higher than the mold. Then fill it with the preparation, and bake for one hour and fifteen minutes in a moderate oven. Let it cool thoroughly for two hours; unmold, place it on a pastry wire-grate, and glaze it the same as for vanilla eclairs. Decorate artistically with a glace royale (No. 101), arranging it in any desired fanciful design. Serve on a dessert-dish, covered with a fancy paper.