Preheat oven to 180 C (gas 4). Line bottom and sides of a 23cm springform cake tin with foil. Grease foil.
Melt margarine and chocolate over low heat. Stir until smooth and let cool.
In a medium mixing bowl, beat whites until stiff; about 2 minutes. In a separate bowl, beat together yolks and sugar until thick and pale; about 1 minute. Blend in chocolate mixture and stir in almonds. Fold in beaten whites, 1/3 at a time, into chocolate until no streaks of white remain. Scrape into prepared tin.
Place a 20cm square baking tin with 2.5cm of water in it on the bottom rack of the oven (to make the torte more moist).
Bake torte on centre rack at 180 C for 45 to 50 minutes, or until sides begin to pull away from tin and top is set in centre. Cover the torte loosely with foil for the last 20 minutes of baking. Note: Don't worry if the cake cracks because the top will be on the bottom later.
Cool on wire rack for 10 minutes and then carefully remove sides of tin. Invert onto a serving plate and cool completely.