Makes 12 servings. This chocolate cake includes bananas both in the cake and creamy sauce. Heat oven to 375 degrees. To prepare cake, grease and flour 8 x 2 1/2 inch springform pan. Heat chocolate and margarine in 1-1/2 quart saucepan until melted. Cool 5 minutes. Beat egg whites and salt in medium bowl on high speed until stiff but not dry. Beat egg yolks and sugar on medium speed until lemon colored. Stir into chocolate. Stir in ground pecans and banana. Gradually fold chocolate mixture into egg whites. Pour into pan. Bake until top is dry and knife inserted in center comes out slightly wet, 40 to 45 minutes. (Do not overbake). Cool completely. Remove from pan. To prepare sauce, beat together bananas, cream, powdered sugar and cinnamon until well blended. Serve cake with sauce, garnished with pecan halves.