Heat the lemon juice and caster sugar in a small heavy-based saucepan over low heat to simmering point, stirring to dissolve the sugar. Add the softened gelatine and stir until dissolved. Strain through a fine-mesh sieve into a heatproof bowl and leave until completely cool but not set.
Whisk the goat’s curd and creme fraiche in a bowl, then add the yoghurt and pe