For feuilletines, combine eggwhite and sugar in a bowl and stir to dissolve sugar. Add flour and stir, then gradually mix in butter. Refrigerate overnight.
Meanwhile, for caramel, heat sugar and glucose in a saucepan over medium-high heat, stirring occasionally, until a dark caramel forms (3-4 minutes). Add butter and ½ tsp salt, swirling pan to combine (be careful, hot caramel will spit), then add cream in batches over low heat and cook, swirling occasionally, until caramel dissolves. Cool completely, then refrigerate until caramel is a spoonable consistency (2 hours).
Meanwhile, for ice-cream, place half the cream in a bowl set over a bowl of ice. Bring milk, vanilla and remaining cream to a simmer in a saucepan. Whisk sugar with yolks until smooth and combined, then pour hot milk mixture over, whisking slowly to combine. Return mixture to a saucepan over medium heat, and stir continuously until mixture thickly coats the back of a spoon (10-15 minutes). Remove from heat, then immediately pour over cream and set aside, stirring occasionally, until cool. Remove vanilla bean, then churn in an ice-cream machine and freeze until mixture starts to firm up (about 1 hour). Working quickly, in batches, fold caramel once or twice only through ice-cream to create a ripple effect, then transfer to a 20cm square cake tin lined with plastic wrap and freeze until firm (overnight). Two hours before serving, turn out ice-cream, cut into 4cm x 10cm pieces and return to freezer until firm.
For praline, preheat oven to 180°C and lightly grease an oven tray. Spread macadamias over another oven tray and roast until light golden (7-9 minutes). Add sugar to a saucepan and heat over medium heat, swirling pan occasionally until a caramel forms (2-3 minutes), then once caramel is deep golden and just starting to smoke, stir through macadamias with an oiled spoon. Pour evenly onto prepared tray and leaveto cool and set (1 hour). Lightly crush praline and store in an airtight container until required.
Meanwhile, bring feuilletine mixture to room temperature. Line 2 oven trays with baking paper and place in refrigerator until chilled. Thinly spread mixture over chilled trays and bake, alternating trays once, until golden brown (7-9 minutes), then immediately score into 4cm x 10cm pieces while still warm. Cool completely, then nfreeze until chilled (20 minutes).
To serve, sandwich ice-cream rectangles with feuilletines and macadamia praline, and top with extra praline.