Apple and blackberry bars with hazelnut crumble

Name: Apple and blackberry bars with hazelnut crumble
Prep time: 35 min
Cook time: 1 h 10 min
Total time: 1 h 45 min
Cuisine: European, British
Ingredients: 150g chilled unsalted butter, chopped; 2 cups (300g) plain flour, sifted; 3/4 cup (165g) caster sugar; 1 egg, lightly whisked; 1 teaspoon vanilla extract; 2 Granny Smith apples, peeled, chopped; 250g fresh or frozen, thawed blackberries; Juice of 1 lime; 1/2 cup (75g) plain flour; 100g chilled unsalted butter, chopped; 1/3 firmly packed cup (80g) brown sugar, plus extra 2 tablespoons to sprinkle; 1/2 cup (45g) rolled oats; 1 cup (125g) roasted hazelnuts, chopped; 1/2 teaspoon ground ginger