Chocolate Caramel Macadamia Tart

In bowl, stir wafer crumbs with butter. Press onto bottom and up side of 9-inch (23 cm) round or square tart pan with removable bottom. Bake in centre of 350°F (180°C) oven for 10 minutes or until set. Let cool completely on rack.

Caramel Filling: In heavy saucepan, bring sugar, water and corn syrup to boil; boil, without stirring, but brushing down side of pan with wet pastry brush, for about 8 minutes or until caramel colour. Remove from heat; whisk in butter, then nuts and cream. Pour into prepared crust. Refrigerate for about 1 hour or until set.

Ganache: In saucepan, heat cream just until boiling; pour over chocolate and butter in bowl, whisking until melted and smooth. Let cool slightly. Pour over caramel filling. Refrigerate for at least 8 hours or until set. (Make-ahead: Refrigerate for up to 2 days.)

Topping: Arrange nuts closely together on foil-lined baking sheet. In saucepan, bring sugar and water to boil; boil, without stirring but brushing down side of pan with wet pastry brush, for 5 to 7 minutes or until caramel colour. Pour over nuts; let cool completely. (Make-ahead: Store, uncovered, for up to 1 day.) Break into pieces; finely chop in food processor.

Remove side of tart pan; slide tart onto serving platter, removing bottom. In bowl, whip cream; spoon into pastry bag fitted with rosette tip. Pipe border of rosettes around edge of tart. Sprinkle with nut topping.