For the sablé pastry

• Unsalted butter 100g
• Plain flour 250g
• Icing sugar 100g
• Egg 1, beaten
• Double cream 10g

For the chocolate filling

• Dark chocolate 450g
• Unsalted butter 300g
• Eggs 6, plus 5 egg yolks
• Caster sugar 80g

1. For the pastry: preheat the oven to 165°c / gas 3.
2. Place the butter, flour and icing sugar in a mixer and paddle mix to a breadcrumb-like consistency.
3. Add the egg and cream and gently mix until just combined.
4. Wrap the pastry in clingfilm and rest for at least 15 minutes.
5. Roll the pastry out on a floured surface to a thickness of approximately 4mm, then use it to line a 20cm tart case.
6. Trim off any excess pastry then freeze the case for 10 minutes. This helps prevent the tart case from shrinking.
7. Line the tart with greaseproof paper and fill with baking beans. Bake in the oven for 12 minutes. Remove the beans and cook for a further 4–5 minutes until lightly coloured.
8. For the filling: melt the chocolate and butter, either in short bursts in a microwave or over a bain marie.
9. Pour the chocolate mixture into a bowl and leave to cool.
10. Place the eggs, yolks and sugar in a mixer and whisk at high speed until the mixture has doubled in volume.
11. Gently fold the egg mixture into the chocolate, one third at a time.
12. Pour the filling into the baked pastry case.
13. Bake in the oven for 10 minutes. The tart will still be wobbly but will firm as it cools.
14. To serve: cut with a hot knife and serve at room temperature.