Preheat your oven to 375 degrees.
Spray a loaf pan with baking spray or grease with butter and flour. Set aside.
Add the butter and sugar to a mixing bowl. Using an electric mixer cream the butter, sugar and vanilla together until fluffy, about 5 minutes. Add in the sour cream and the eggs one at a time, making sure each is fully incorporated.
Add in the flour and baking soda and mix until just combined. do not over mix.
Pour into prepared pan and bake for 50-60 minutes or until an inserted toothpick comes out clean. Cool completely and dust with confectioners sugar before serving.