Buche de no l(christmas log cake)

-----CAKE-----
   1       c            Cake flour, sifted
     1/4   ts           Salt
   1       t            baking powder
   4                    Egg
   1       c            Sugar
     1/4   c             -- water
   1       tb           Lemon juice
                        -----meringue MUSHROOMS-----
   2                    Egg white
     1/4   c            Cream of tartar
     1/4   c            Sugar
                        Cocoa, powdered
                        -----butter CREAM-----
   1       c            butter, sweet -- softened
   3                    Egg yolk
                        -----ICING-----
   1       tb           Espresso, powdered
   1       tb           Milk
   3       c            Sugar, confectioners -- sifted
                        Food coloring, green

  Grease a jelly roll baking sheet.  Line with parchment
  paper. Grease the parchment paper.  Sift dry
  ingredients together.  Beat eggs at high speed about 5
  to 10 minutes.  Add sugar by tablespoonfuls. Continue
  beating until the butter is very thick. Then add lemon
  juice and water. Fold in dry ingredients in four
  stages, 1/4 cup at a time. Spread evenly on the baking
  sheet.  Bake at 375 F. for 15 minutes or until the
  sponge springs back when tested.  Sift powdered sugar
  onto the sponge. Turn cake out onto a clean tea towel.
  Remove parchment paper. Trim edges of the sponge if
  they are crispy.  Roll up gently, leaving towel
  inside, while still warm. Let cool. Beat egg whites,
  and when foamy add the cream of tartar.  When soft
  peaks form, gradually beat in the sugar.  Beat until
  meringue is stiff and glossy. Pipe meringue through a
  pastry bag, making and equal number of stems and caps
  to resemble small mushrooms.  Bake mushroom pieces at
  250 F. about 45 minutes.  When cool, glue them
  together with butter cream icing and dust lightly with
  cocoa in a fine strainer. Beat egg yolks and butter
  together until smooth.  Add coffee and milk. Gradually
  add powdered sugar. Beat until smooth.  Mix about 1/3
  cup to 1/2 cup of the frosting with green food
  coloring for the ivy decoration. TO ASSEMBLE: Unroll
  cooled sponge, remove towel, spread, cake with butter
  cream icing. Roll up. Cut off at a diagonal, a 2"
  slice. This is the tree stump. Frost the outside, then
  add the stump and frost. Make ivy patterns. Add the
  mushrooms. Dust the whole cake very lightly with
  powdered sugar, to simulate snow. Keep in
  refrigerator. Cut with serrated knife.