Preheat oven to 180°C and line two baking trays with parchment paper.
Combine the butter, vanilla and sugars together in the bowl of a stand mixer with the paddle attachment and cream for five minutes or until pale and fluffy.
Add the eggs, one at a time, beating well after each addition.
Sift in the flour, salt and bicarb soda and fold together. Add the chocolate and nuts and fold again until just combined.
Let the mixture rest in the fridge for 20-30 minutes.
Using an ice cream scoop or tablespoon, scoop even amounts of the biscuit dough onto your prepared tray, leaving space for them to spread a little.
Bake for 15 minutes or until the biscuits are golden brown. Transfer to a wire rack to cool then store in a jar or airtight container for a few days.