While the marshmallows are drying out, we will prepare a mousse.:
Break the chocolate into pieces and add water, put on medium heat (about 3) and cook the mixture until the chocolate dissolves, do not heat too much! Pre-prepare a deep bowl with ice water and ice cubes, put it back in the mold and beat with a mixer. (I decided to add a mousse recipe with great photos)
The first stage: nothing happens, just foam.