2 1/4 cups sifted confectioners' sugar
3 egg whites
Green paste food coloring

Chocolate Buttercream
1/3 cup butter, softened
3/4 cup sifted confectioners' sugar
1 1/2 tablespoons cocoa
1/2 teaspoon vanilla extract
1 to 2 teaspoons milk

Line two large baking sheets with wax paper. Sketch 24 (3-1/2 inch tall) Christmas trees onto paper. Set aside.

Combine confectioners' sugar and egg whites in top of double boiler. Beat at low speed with an electric mixer 30 seconds or just until blended. Place over boiling water. Beat constantly at high speed 5 to 7 minutes or until peaks form. Remove from heat.

Fit No. 22 tip into decorating bag. Using a small art brush, paint a 1/4-inch wide strip of food coloring inside bag from tip to outer edge. Fill with meringue mixture. Starting at top of drawn trees, pipe meringue mixture to resemble trees, using zigzag motion, with green stripe showing. Bake at 300 degrees F for 25 minutes. Cool on baking sheets.

Carefully peel away wax paper, and store trees in an airtight container at room temperature up to 2 days.

Pipe or spread Chocolate Buttercream on flat sides of half of trees, and top with remaining trees. Serve immediately.

For Chocolate Buttercream: Beat butter at medium speed with an electric mixer until creamy. Gradually add sugar, beating well. Add cocoa, vanilla extract and milk; beat until mixture reaches spreading consistency.