Let eggs, butter, and sour cream come to room temperature (about 45 minutes)
In a mixing bowl, beat the butter with the eggs and sour cream.
Add remaining ingredients and beat just until well mixed.
Pour batter into a greased and floured loaf pan (or a 9 by 9 inch square)
Bake in a 325 degree oven for 60 minutes or until toothpick inserted in center comes clean.
Cool before serving.