Preheat your oven to 180C (350F). Place walnuts on a baking tray and roast for 8-10 minutes or until deeply golden brown and tasting toasted.

Line a loaf tin with baking paper so the base and sides are covered. Bring cream to a simmer in a medium saucepan. Remove from the heat and stir in the chocolate chunks. Stand for about 5 minutes to allow chocolate to melt.

Gently stir your chocolate cream mixture until smooth and glossy. If there are a few chunks of unmelted chocolate don’t stress too much.

Pour half the chocolate mixture into your prepared tin. Top with 3/4s of the walnuts saving the last 1/4 for decorating the top. Layer over the remaining chocolate mixture. Finish with the remaining walnuts.

Place in the freezer for 6 hours or until the ‘cake’ has set enough that you can slice it.