Crush all the Tim Tams separately and place into three separate bowls so the original Tim Tams are in one, the white chocolate Tim Tams in the other and the dark chocolate Tim Tams in the last one.
Pour a third of the condensed milk into each of the bowls.
Mix the Tim Tams with the condensed milk until gooey. (Ensure you rinse the spoon between bowls).
Roll the mixtures into balls and place on a non stick baking sheet on a baking tray and place in the freezer for half an hour.
Melt the three chocolate flavours separately and dip each truffle into the chocolate.
You can either use the chocolate flavour to the corresponding truffle flavour or mix it up and dip the truffles at random.
Place in the fridge until the chocolate has set.
Store in the refrigerator for up to two weeks.
Notes
You can just use one packet of Tim Tams if you want a smaller amount of truffles. You can use all the same flavour of Tim Tams and chocolate if you prefer.