Bet you can’t eat just one slice! Once you sink your fork into this super-moist treat, you’ll understand why!
In the bowl of an electric mixer fitted with a baddle attachement, cream the butter and sugar on medium-high speed until well mixed.
Add the eggs, one at a time, and beat until incorporated. Scrape down the sides of the bowl once or twice.
Add the vanilla and then alternate adding the sour cream with the dry ingredients until mixed. Scrape the bottom of the bowl once or twice while mixing.
To make the filling: mix together the walnuts, sugar and cinnamon.
Spoon half of the batter into the 3 x 9 x 5 inch loaf pan. Sprinkle half of the filling over the batter and then add the rest of the batter to the pan.
Sprinkle the rest of the filling over top of the loaf. Bake for 55 to 60 minutes or until a toothpick inserted in the center comes out dry.