Step 1

Preheat oven to 180°C. Lightly oil the base of a 23cm springform cake pan and line with baking paper. Spread nuts on a baking tray and roast for 5-6 minutes or until golden. Remove and cool. Place in a food processor and pulse until coarse crumbs. Remove and set aside, then add the biscuits to the processor and process to coarse crumbs (or place in a plastic bag and crush with a rolling pin).

Step 2

Combine the nuts, biscuits and glace orange in a bowl. Melt the chocolate in a heatproof bowl set over a pan of gently simmering water, making sure the bowl doesn't touch the water, then cool slightly.

Step 3

Place the eggs, extra yolks and sugar in the bowl of an electric mixer and beat for 5-6 minutes until thick and pale. Slowly add the butter with the mixer running. Beat in the cooled chocolate and fold in the biscuit mixture.

Step 4

Pour into the prepared pan, then refrigerate for 4 hours or until firm. Transfer to a serving plate, dust with cocoa and cut into wedges to serve.