Begin by dry-frying the hazelnuts (with no oil) until they start to colour. Leave to cool, then remove the brittle skins by stirring the nuts vigorously or rubbing them in your hands (be careful if still hot). Remove as much of the skins as possible. Then place the nuts in a blender and reduce to a powder.
Chop the chocolate using a knife and place in a bowl over a water bath. Once the chocolate has melted, incorporate the condensed milk, mix well and take the bowl off the heat. Add the diced butter and stir gently. Then add the powdered nuts, vanilla and tonka bean and mix together. Pour the mixture into sterile jar and fill them generously. Secure the lids and allow to cool right down.
We would advise you to store jars in the refrigerator and remove a day before opening to ensure that the spread is nice and soft. If this is too large a quantity, you can divide the ingredients by 2 or 4!
We have included butter in the recipe to create a rich and creamy spread, so there is no need to butter your bread. Just enjoy the spread!