- 25g/1oz butter
- 50g/2oz rhubarb, chopped
- 3 tbsp soft brown sugar
- 1 vanilla pod, seeds scraped out
- 2.5cm/1in piece root ginger, peeled and chopped
- 50g/2oz plain flour
- 25g/1oz cold butter, chopped
- 2 tbsp caster sugar
- 3 free-range egg yolks
- 4 tbsp caster sugar
- pinch arrowroot
- 500ml/17fl oz milk
- 1 tsp vanilla essence
- Preheat the oven to 180C/350F/Gas 4.
- For the filling, heat the butter in a pan, add the rhubarb, sugar, vanilla seeds and ginger and cook gently for five minutes, or until softened. Pour into a small ovenproof dish.
- For the crumble topping, place the flour and butter into a blender and pulse until the mixture resembles breadcrumbs. Stir in the sugar, then sprinkle the crumble topping over the rhubarb mixture.
- Place on a baking tray in the oven and cook for 10-12 minutes, or until just turning golden on top.
- Meanwhile, for the custard, place the egg yolks, sugar and arrowroot into a large bowl and whisk until pale and fluffy.
- Meanwhile, heat the milk in a non-stick pan until just below boiling point. Pour the hot milk over the egg mixture and whisk continuously until well combined. Pour the mixture back into the pan and stir over a low heat until thickened.
- To serve, spoon the crumble into serving bowls and pour over the custard.