Kat's Nutty Nut Cake

As made by our friend Kat, for a little gathering we had at our friend Joelle's ... very nice it was too:

150g chopped Hazelnuts (it says Walnuts, but that's a transcription error)
2 dl (decilitre, i.e. 200ml) sugar
3 eggs
Mix all the above.

Put in oven (175 degrees) for 30-45 min.
Then let cool down.

For the caramel sauce, boil up:
1.5 dl cream (150 ml)
2 full table spoons syrup

When it gets a bit thicker, add:
0.5 table spoon butter
2 table spoons vanilla sugar (apparently a Swedish thing, normal sugar is fine if you can't get it)

Pour it over the cake and leave it to set.