For the posset, bring the cream and sugar to the boil in a saucepan. Remove the pan from the heat, then whisk in the lemon zest and juice, whisking as much air into the mixture as possible.
Pour the posset mixture into ramekins and chill in the fridge for 1 hour, or until set. Once set, decorate the tops with strawberries, figs and mint sprigs.
For the shortbread, preheat the oven to 180C/160C Fan/Gas 4.
Mix the plain flour, icing sugar, ground almonds and cornflour together into a bowl. Rub the butter into the dry ingredients until the mixture resembles breadcrumbs, then gently bring the mixture together as a dough.
Divide the dough into 24 small, equal-sized balls and press one into each well of a 24-hole silicone fairy cake mould (or two 12-hole ones). Alternatively roll out the dough to about 1cm/½in thick and use a small biscuit cutter to cut out shapes.
Bake the shortbreads in the oven for 10-12 minutes, or until pale golden-brown.
While the shortbreads bake, bring the jam to the boil in a saucepan with 50ml/2fl oz water. Reduce the heat and simmer for 2-3 minutes, or until the mixture resembles a thick syrup.
Remove the shortbread from the oven and, when cool enough to handle but still malleable, make a small dent in the centre of each with your finger.
Spoon the warm strawberry syrup into the dent in each shortbread, then remove them from the moulds and set aside to cool on a wire rack. Serve the shortbread alongside the lemon possets.