Bake tart cases according to pack directions. Leave on oven tray and set aside to cool. 

Chop butter and place with Pauls Premium Vanilla Custard sugar and salt into a medium saucepan over a medium heat to simmer. Stir constantly for 5 minutes or until very thick and then immediately divide the mixture between the 12 tart cases. Refrigerate for 1 hour or until cool.

Place chocolate in a heatproof bowl and place over a saucepan of simmering water, making sure that the water does not touch the base of the bowl. Stir occasionally until melted. 

Drizzle chocolate onto tarts either with a spoon or through a piping bag. Refrigerate until set. Store in the refrigerator.