Heat the oven to 190°C or 375°F.
Chop dark chocolate and Toblerone and set aside.
Cream together butter and sugar. Once it's nice and light add the egg and combine before stirring in the vanilla sugar.
Add the remaining dry ingredients to the wet ingredients and just before it all comes together add the chocolate. Do not overmix.
Form the dough into small rounds and place on the cookie sheet with room to spread out as they flatten in the oven.
Bake for 8-10 minutes. The centres should still be gooey.
Allow them to firm up a minute or two on the pan before attempting to move them to a cooling rack.
I like small cookies but you could certainly make 12 larger ones that would likely be extra gooey.**I tend to pre-portion and place several on parchment in the freezer until they firm up (so they don't freeze together) and then I throw them into a freezer bag or container until I'm ready to bake them that way I always have snacks at the ready. Place frozen cookies directly into a preheated oven for 9 or so minutes at your convenience! ***Note that you can also substitute 1 tsp vanilla extract for the vanilla sugar.
