01 - Place chopped dark chocolate in a heatproof bowl set over simmering water, stirring constantly until completely smooth. Remove from heat and allow to cool for 5 minutes until lukewarm.
02 - In a chilled mixing bowl, beat heavy cream with electric mixer until soft peaks form. Refrigerate immediately until ready to incorporate.
03 - Whisk egg yolks with vanilla extract in a separate bowl until pale and slightly thickened. Gradually fold in cooled melted chocolate until fully incorporated and glossy.
04 - Using clean beaters, whip egg whites with salt until soft peaks appear. Slowly add granulated sugar while continuing to beat until stiff, glossy peaks form that hold their shape.
05 - Gently fold whipped cream into chocolate-yolk mixture using a spatula. Carefully fold in beaten egg whites in three additions, maintaining as much air as possible until no white streaks remain.
06 - Distribute mousse evenly among serving glasses. Refrigerate for minimum 2 hours until completely set and firm to the touch.
07 - Combine fresh raspberries, powdered sugar, and lemon juice in a blender. Process until completely smooth, approximately 1 minute.
08 - Press raspberry purée through a fine-mesh sieve using a spatula, extracting all liquid while removing seeds. Refrigerate until serving time.
09 - Spoon chilled raspberry coulis over set chocolate mousse. Garnish with fresh raspberries, chocolate shavings, and mint leaves as desired. Serve immediately.