Combine chocolate, boiling water, and ¼ cup sugar; stir until chocolate is melted.
In large bowl, sift together flour, sugar, baking powder, and salt. Make a well in center of the dry ingredients and add cooking oil, egg yolks, cold water, and vanilla in order given. Beat until very smooth.
Stir the chocolate mixture into the egg yolk mixture.
In large bowl, beat egg whites with cream or tartar until very stiff peaks from. Pour chocolate batter over entire surface of egg whites, folding gently to blend.
Bake in greased 12-Cup Bundt Pan at 325 degrees for 50 -55 minutes or until cake tests done. Cool in pan 10-15 minutes; turn out on serving plate to complete cooling.
Soften gelatin in cold water.
Heat together crème do cocoa and crème de menthe. Add softened gelatin. Stir until gelatin is dissolved. Cool.
Whip cream, fold in gelatin mixture.
Refrigerate 15 minutes.
Split cooled cake crosswise into three layers. Spread ½ of filling between layers; place remaining ½ in center and on top of cake.