Rinse the muslin cloths, squeeze dry and line the moulds with them, letting them overhang on the sides.
Using hand held beaters, beat the cream until the soft stage. Be careful here and run at low speed at the end, because it's a very fine line between the final soft stage to the stiff stage. Set aside.
With the same beaters, cream the mascarpone, lemon juice, sugar and vanilla until well mixed and smooth.
Gently fold in the cream in 2 additions and mix well.
Spoon this cheese mix into the individual moulds or whatever you're using, flattening the top.
Tap the moulds on the table a few times, to level out and release any trapped bubbles and fold the muslin over, as in picture.
Place the moulds on a baking sheet or a tray and place in the fridge overnight or for a minimum of 6 hours.
About 10-20 minutes before serving, turn them out and let them rest at room temperature. I find this allows the flavour to come through better.
Spoon some coulis and decorate with fruit as you wish, some mint or basil will go nicely as well, for colour and flavour contrast