Preheat oven to 180 degrees celsius (fan-forced). Place pre-made shortcrust pastry shell onto a baking tray and set aside.
Arrange half of the pecans on the base of the tart shell.
Place the butter into the Thermomix bowl and melt on Speed 2, 100 degrees, 2 minutes. Allow to cool.
Add the eggs, maple syrup, brown sugar, self raising flour and vanilla bean paste. Mix on Speed 6 for 30 seconds.
Carefully pour the mixture into the tart shell (not quite to the top). Add the remaining pecans and press down lightly into the mixture.
Bake in the oven for 20-25 minutes or until golden and cooked through.
Serve warm or cold (with ice-cream or cream).