Method

• 1.
  Preheat oven to 180°C/160°C fan-forced. Grease base and side of a 20cm round springform pan and line base and side with baking paper.
• 2.
  For the apples, melt salted butter in a large ovenproof frypan over medium-high heat. Cook apple, tossing often, for 15 minutes, or until golden. Place on the bottom rack of the oven and roast for 25 minutes. Set aside in pan until ready to assemble.
• 3.
  Meanwhile, to make the cake, whisk salted butter, sugar and vanilla in a large bowl until pale and combined. Add eggs and whisk until combined. Combine flour, baking powder and mixed spice in a medium bowl. Sift half the flour mixture over the egg mixture, then stir until partially combined. Add half the milk and stir until just combined. Repeat with remaining flour mixture and milk. Pour into prepared pan. Bake for 35 minutes on a high oven rack, or until a skewer inserted in centre comes out clean.
• 4.
  Meanwhile, to make the caramel, place sugar in a medium non-stick saucepan over medium-high heat. Cook, swirling pan, for 5-7 minutes, until sugar has completely dissolved and mixture is a golden caramel colour. Reheat to low. Add unsalted butter and swirl to melt the butter, then add cream. Bring to a simmer over medium-high heat, stirring until completely smooth. Simmer for 2 minutes, to thicken slightly. Remove from the heat and stir in the whisky. Set aside to cool slightly.
• 5.
  Stand cake in pan on a wire rack and immediately poke holes all over the top with skewer. Drizzle over 1 1/2 tbs caramel. Arrange apple on top and set aside for 30 minutes to cool.
• 6.
  Transfer cake to a serving platter. Serve warm or at room temperature, drizzled with remaining caramel and a dollop of creme fraiche, if using.