Stir together the flour, baking soda, and spices. Set aside.
In a large mixing bowl, beat together the sugar and butter with an electric mixer until fluffy.
Add eggs, one at a time, beating well after each addition.
Add the dry ingredients and the sour cream alternately to the beaten mixture, beating until just combined.
Turn batter into a greased and floured 9x5x3-inch loaf pan or two 7-1/2x3-1/2x2-inch loaf pans.
Bake in a 350 degree F oven for 55 to 60 minutes for the large loaf or 45 to 50 minutes for the two smaller loaves. Let cool in pan(s) on wire rack(s) for 10 minutes. Remove; cool. Makes 1 or 2 loaves.