In a small saucepan, bring coffee to boil and add couscous. Cover, remove from heat and let sit for 10 minutes.
Meanwhile, gently melt chocolate chips in a bowl over a pot of simmering water (or in the microwave). Set aside 1/3 cup (80 ml) of the melted chocolate.
In a blender, whip yogurt, tofu and melted chocolate (except for set-aside quantity) until smooth.
Fluff couscous with a fork. Mix in remaining melted chocolate with a rubber spatula, and press mixture evenly onto bottom of a 9-inch/23-cm spring-form pan.
Pour yogurt mixture over crust. Refrigerate torte overnight. Serve torte cold with your favourite garnish such as toasted pecans, or fresh strawberries or raspberries.