Cream butter and sugar together for 5 to 7 minutes
Add in eggs one at a time
Mix until thoroughly incorporated
Sift cake flour and baking powder together
Alternate adding in flour and baking powder mixture and sour cream, milk and vanilla mixture
Mix just until incorporated
Grease loaf pan
Preheat oven to 350 °F
Bake pound cake for approximately 1 hour, or until toothpick inserted in the center comes out clean
Let pound cake cool for approximately 10 to 15 minutes before removing it from loaf pan
Finish cooling on wire rack
Wrap pound cake in plastic wrap and store at room temperature for 4 to 5 days