1: Put the cream and vanilla pods into a heavy-bottomed saucepan and bring just to the boil. Take the pan off the heat and leave to stand for 30 minutes.
2: Bring the infused cream back up to a simmer. Meanwhile, in a bowl, whisk the eggs and erythritol together to combine. Pour on the hot vanilla cream, whisking as you do so, then pour the vanilla custard back into the rinsed-out saucepan.
3: Cook the custard, stirring constantly with a wooden spoon, over a medium-low heat until it thickens enough to lightly coat the back of the spoon; it should register 87°C on a cook’s thermometer.
4: Pass the custard through a fine sieve into a bowl and leave to cool for 20 minutes.
5: Once cooled, scrape the custard into a blender and blitz for 20 seconds - this will give it a nice, glossy finish.
6: Divide the mixture between 6 ramekins or similar heatproof serving dishes. Refrigerate for at least 4 hours, or overnight, to set.
7: When you’re ready to serve, sprinkle the inulin on top of the set custards in a nice, even layer. Using a cook’s blowtorch, caramelise the inulin until it forms a deep, caramel crust (or place briefly under a preheated very hot grill). Leave for a minute or so to allow the glaze to set before serving.