1. Heat the cream over very low heat in a small non-stick saucepan.
2. Incorporate the white chocolate pieces, a little at a time. Make sure the preparation is smooth and homogeneous. Remove the saucepan from the heat, let it cool, then place the mixture in the refrigerator for at least 2 hours.
3. A few minutes before serving, remove the cream from the refrigerator and beat it with an electric mixer.
4. Divide the mousse into glass cups and place the lychees on small wooden sticks that you will use as decorations. Pour a little lychee syrup and refrigerate before serving.