This came about because I had a punnet of beautiful fat blackberries which I'd bought half price but without a plan. They don't store for long, so I had to come up with something, and I spotted half a tub of fat-free fromage frais in the fridge. It ended up as a very light, fresh-tasting mousse with a layer of slightly-too-rubbery but beautifully coloured and flavoured jelly on top. It has very few ingredients but does generate quite a lot of washing up.
Bramble fromage frais mousse (serves 2-4, depending on size of your glasses)
3 tbs caster sugar
3 leaves gelatine, divided use
250g fat-free fromage frais
1tbs Chambord or Crème de cassis or Crème de mûre
Reserve 2-4 (depending on number of portions you are making) of the prettiest blackberries, then puree the rest (I used a stick blender). Sieve the puree, and discard the detritus. It should yield about 150ml of puree.
Place 2 of the gelatine leaves in a bowl of cold water. Whisk the egg and sugar in a heat-proof bowl over a bain marie until the sugar dissolves and the mixture more than doubles in volume. Squeeze the water out of the gelatine sheets and add it to the egg mixture, continuing to whisk.
When the gelatine has completely dissolved, remove the bowl from the bain marie, whisk in the fromage frais and 100ml of the blackberry puree. Divide between your serving glasses, making sure you leave about 1cm of head room on each one. Refrigerate for half an hour.
At the end of the half hour, put the last leaf of gelatine to bloom in cold water for 5 minutes, then put the remaining blackberry puree and Chambord in a small saucepan and warm gently until just beginning to bubble at the edges. Squeeze out the gelatine sheet and add to the blackberry mixture and stir until completely dissolved. Spoon the jelly mixture carefully over the surface of the mousse to completely cover. Refrigerate another half hour, then garnish with the blackberries (needs a little setting time before you add the blackberry garnish or they'll sink straight through). Chill for a couple of hours or overnight before serving.