1.Preheat oven to 150°C (130°C fan-forced).
2.Grease a deep 20cm square or a deep 23cm round cake pan; line base and side(s) with 4 thicknesses of baking paper, extending paper 5cm above sides of pan.
3.Meanwhile, to make caramel: Place sugar in a small heavy-based pan; stir over medium heat for about 5 minutes or until sugar melts and turns a light golden brown, do not stir. Remove from heat; carefully add water (mixture will spit hot sugar). Return to low heat; stir until any pieces of toffee are dissolved. Cool caramel until warm.
4.Reserve 30g of the nuts for decorating the cake, if desired. Combine remaining nuts, fruit, peel and sherry in a large heatproof bowl; mix well. Stir in warm caramel mixture.
5.Beat butter, sugar and vanilla in a small bowl with an electric mixer until combined. Add eggs, one at a time, beating well after each addition. Add butter mixture to fruit mixture; stir until well combined. Stir in flour.
6.Spread mixture into pan. Decorate with reserved almonds. Bake for about 2¼ hours or until cooked when tested. Cover with foil, wrap in a clean towel; cool in pan overnight.
For those who prefer a light fruit cake, this is ideal. Keep the cake for 3 to 4 days before cutting, then cut with a sharp serrated or electric knife to cut cleanly through the almonds.Note