In medium bowl, combine cocoa with boiling water, mixing with wire whisk until smooth.

Cool completely.

Sift flour with soda, salt and baking powder.

Preheat oven to 350°F.

Grease well and lightly flour three 9 by 1 ½ inch layer-cake pans. For one 12-inch pan, line with parchment paper

In large bowl of electric mixer, at high speed, beat butter, sugar, eggs, and vanilla, scraping bowl occasionally until light-about 5 minutes.

At low speed, beat in flour mixture (in fourths), alternately with cocoa mixture (in thirds), beginning and ending with flour mixture. Do not overbeat.

Divide evenly into pans;smooth top. Bake 25 to 30 minutes, or until surface springs back when gently pressed with fingertip.

Cool in pans 10 minutes.

Carefully loosen sides with spatula; 4. Remove from pans; cool on racks.

Frosting: In medium saucepan, combine chocolate pieces,cream, butter;stir over medium heat until smooth.

Remove from heat.

With whisk, blend in 2 ½ cups confectioners' sugar.

In bowl set over ice(I use ice cubes) beat until it holds shape.

Filling: whip cream with sugar and vanilla;refrigerate.

To assemble cake: On plate place a layer, top side down;spread with half of cream.

Place second layer, top side down;spread with rest of cream.

Place third layer, top side up. To frost: With spatula, frost sides first,covering whipped cream;use rest of frosting on top, swirling decoratively.

Refrigerate at least 1 hour before serving.

To cut, use a thin-edged sharp knife;slice with a sawing motion.

And forget the swirls.

I think it looks gourmet just to spread the frosting.

It dries really dark and looks cool.

Somethimes I just drag a sharp knife across the top in lines and sometimes I leave it as it is. From McCall's Cooking School.