5: Begin assembling the charlotte: soak a biscuit in the syrup...
6: ...and place on the paper in the bottom of the mould. Use as many biscuits as you need to form what will become the "top" of the charlotte. The biscuits should sit tightly against each other (press them into place if necessary). The bottom of the mould should no longer be visible. Fill in any gaps with small pieces of soaked biscuit.
7: Then arrange biscuits vertically up the sides, soaked as before, to form the sides of the charlotte. The sides of the mould should be completely covered with a tightly packed layer of biscuits.
8: Put the first layer of cream in the bottom of the mould.
9: Cover with a layer of strawberries.
10: Continue filling with alternating layers to the top of the mould.
11: Finish with a final layer of biscuits. It is fine to leave the top rounded (more than in the photo), as the charlotte will compact as it stands cover with stretch plastic film and put in the fridge for at least 2 hours. Make a coulis with any left-over strwaberries and keep this in the fridge, also covered with plastic film.
If you intend making your charlotte a day or two in advance, I advise you to add a sheet of gelatin to the whipped cream which will help it keep better. You can add a tablespoon of rum to the syrup or make it with brown, rather than white sugar - it's simply a matter of taste.