Line a baking dish of choice with parchment paper. I like to use a round cake tin for easy serving.
Bring a pot of water to a boil then lower to a simmer and add chocolate chips to a heat safe bowl over the pot (bain marie method). Whisk continuously until the chocolate chips melt completely and the mixture is smooth.
Remove the bowl from the heat and whisk in pumpkin purée until smooth. Transfer this mixture to your baking dish or cake tin and smooth the top layer so it's nice and even.
Let set in the fridge for 3 hours or overnight. To serve, slice and sprinkle with flaky salt (optional).