Preheat oven to 325°F. Grease and flour a 12-cup bundt pan.
Cream the butter and sugar together until light and fluffy.
Add eggs one at a time, beating well after each addition.
Whisk together flour, baking soda, and salt in a separate bowl.
Add dry ingredients to the creamed mixture alternately with buttermilk, beginning and ending with flour.
Stir in vanilla and pour batter into prepared pan.
Bake for 70–80 minutes or until a toothpick inserted comes out clean.
Cool in pan for 10 minutes, then invert onto a wire rack to cool completely.