For the base, gently melt the creamed coconut in a pan, stirring regularly.
Use a food processor to blitz the biscuits into crumbs.
If you aren’t using a food processor, bash them in a bag with a rolling pin. Mix with the melted coconut and a pinch of salt.
Press over the base and up the sides of a 22cm round loose-bottomed fluted tin. Chill.
Bring the coconut milk nearly to a simmer.
Meanwhile, whisk together the egg yolks, caster sugar and flours.
Pour the coconut milk over while whisking.
Tip back into the pan and gently heat, stirring constantly, until thick and smooth.
Simmer for 2 minutes then remove from the heat and stir in the rum.
Cool with a sheet of cling film laid directly on the surface so a skin doesn’t form.
Scrape the caramel into a pan with the chocolate, broken into chunks, and gently melt together.
Peel and slice the bananas, then arrange the slices over the base of the pie.
Pour over the chocolate caramel and chill to set – for 1 hour minimum but overnight is best.
When the coconut cream is cold, scrape into a bowl with the double cream and beat until just thick enough to form a peak.
Gently spoon into a plastic food bag and chill until ready to serve.
To serve, snip off the end of the cream bag and pipe all over the pie.
Dust with a little cocoa to finish and if using, the hazlenuts.