ramekinsor other small containers to put mousse in
Make the Chocolate Mousse:
In two separate bowls, separate the egg whites from the egg yolks. In case you do not know how to do this, I linked a video tutorial in the notes.
In a small pot on low heat, break the baking chocolate bar into small pieces and melt the chocolate, stirring frequently.
Add egg yolks and mix well. Remove from heat transfer into a large mixing bowl.
In a separate mixing bowl, beat egg whites until stiff peaks are formed. Start the hand mixer on slow and increase the speed every 1-2 minutes. This process will take around 10 minutes.
Using a rubber spatula, add a small amount (about 1/2 cup) of the egg white into the mixing bowl with the chocolate. slowly fold chocolate into egg whites. Once egg whites are fully incorporated, add some more egg whites. Continue doing this until all the egg whites are combined. The mousse should resemble a smooth, pudding-like consistency.
Spoon the mousse into ramekins and top with berries. Place in fridge for at least 1 hour to set.
Make the Caramel:
In a small pot on low heat, combine sugar, butter, and milk. Stir frequently until sugar is dissolved (about 1-2 minutes).
Remove from heat and stir in vanilla. Caramel sauce will thicken as it sits.
Remove chocolate mousse from the fridge and top with caramel sauce. Dust with powdered sugar (optional).