Preheat the oven to 350 and butter two 9 x 5 loaf pans.
In a large bowl cream together butter, sugar and orange zest.
1 cup butter, 1 ½ cups sugar, 3 teaspoons orange zest
Add vanilla and add in eggs one at a time, mixing after each addition.
½ teaspoon vanilla extract, 3 eggs
In a medium bowl combine the flour, baking powder and salt.
2 ½ cups all-purpose flour, 2 teaspoons baking powder, 1 teaspoon salt
Add half of the flour mixture to the butter mixture and mix until well incorporated.
Add in sour cream and orange juice and mix well.
¾ cup sour cream, 2 Tablespoons orange juice
Add in remaining dry ingredients and continue mixing until everything is well mixed.
Fold in the cranberries with a spatula or wooden spoon until evenly distributed.
2 ½ cups fresh cranberries
Evenly distribute the batter between the two pans and spread it out.
Bake for 55-60 minutes or until a toothpick or cake tester placed in center comes out clean.
Allow the cakes to cool for about 30 minutes in the pans, then remove them from the pans and allow to cool completely on a wire rack before glazing. (about 30 minutes)