Dark chocolate & Persian lime tart

1. Blitz the digestives and nuts together in a food processor, or crush them by putting them in a large plastic food bag and bashing with a rolling pin until they are the consistency of breadcrumbs. Transfer to a bowl, add the melted butter and mix well. Press the crust mixture onto the base of a 20cm loose-bottomed fluted tin, then transfer to the fridge to chill.  

2. Crack the dried limes by hitting them with a rolling pin, then place them in a small saucepan along with the double cream and sugar. Stir to combine, then leave to infuse over a very low heat for 10 minutes, stirring occasionally. Watch the pan, as you don’t want the cream to come to the boil.

3. Half-fill another pan with just-boiled water. Put the chocolate into a large bowl and place on top of the pan without it touching the water. Use a sieve to strain the cream mixture into the chocolate, pressing against the pieces of dried lime with a wooden spoon to extract their flavour. Stir until the chocolate melts and you have a thick, glossy filling. Add the vanilla extract and a pinch of sea salt flakes.

4. Spoon the chocolate ganache into the pie crust. Use a spatula to smooth it out, then sprinkle over the rose petals. Transfer to the fridge and chill for at least 1 hour, or until set.