Mix the butter until it has a cream-like consistency.
Add sugar and mix well.
Add a beaten egg little by little and mix it all in (It will separate if you add it all at once, so add a bit and mix and repeat).
Add the cream and mix everything together.
Add the flour and mix gently without kneading.
It's fine if it ends up a bit floury like in the photo. You can add vanilla extract here if you like.
Roughly break up the nuts and chocolate.
Then mix them into the dough.
Even if it was a bit floury in Step 6, make sure you mix it to a good consistency here.
Use a spoon to drop pieces of the dough onto a baking sheet lined with parchment paper.
Use the back of a fork to flatten them, and bake in a 170 (340) oven for 15-20 minutes.