Photograph: Philip Webb / Peter Cassidy
Preheat the oven to 160°C, fan 140°C, gas 3. To make the compote, put the cranberries in a small saucepan with the orange zest and gently cook over a low heat for 5-8 minutes. Add the 50g caster sugar and heat for a few minutes more, stirring occasionally, until the sugar has melted and blended to a syrup with the juice. Transfer to a bowl, remove the orange zest, then leave to cool.
Whiz all the ingredients for the custard, except the icing sugar, in a blender, and pass through a sieve into a bowl or jug. Divide slightly less than half the compote between the ramekins, then divide all the custard mixture between them. Place in a roasting tin with hot but not boiling water that comes two-thirds of the way up the sides of the ramekins, and bake for about 1 hour or until lightly golden and set. If you move a ramekin from side to side, the custard should wobble, but there should be no sign of liquid beneath the surface. Remove the ramekins from the tin and leave to cool to room temperature.
Gently heat the sugar for the caramel in a small pan until about half of it has liquefied and started to colour, then stir it. Keep a careful eye on it, stirring frequently, until it is a deep gold, then remove from the heat. Dust the surface of each crème with icing sugar, using a tea strainer, then drizzle a teaspoon of caramel over each one. It should set hard within minutes. Cover and chill in the fridge for a couple of hours.
To serve, top each crème brûlée with the remaining compote and orange zest.
Get ahead: make the compote and brûlées up to 2 days ahead, drizzle with caramel and chill before serving.