Preheat the oven to 180°C, then line an 8-inch square baking pan with enough parchment paper to overhang the edges, and set aside.
Using an electric mixer, beat the butter and sugar until combined, then beat in the vanilla. Stir in the flour and chopped TWIX® Twin Bars. Press into the bottom of the prepared pan, and prick all over with a fork. Freeze for 10 minutes.
Bake for 8 to 10 minutes or just until set and pale golden around the edges. Allow to cool completely, then spread the apple pie filling on top.
For the streusel topping, stir together the pecans, flour, brown sugar, cinnamon, nutmeg and cloves. Rub in the butter with your fingertips until blended. Add the chopped TWIX® Twin Bars, and toss well.
Sprinkle the streusel topping over the filling. Bake for 25 to 35 minutes or until golden brown and bubbling. Allow to cool completely.
Using the parchment paper as handles, transfer to a cutting board. Cut into 12 bars.
Tip: Serve with a scoop of vanilla ice cream if desired.