1 and 1/2 cups unsalted butter (softened)
3 cups sugar
4 eggs at room temperature
3 cups unsifted flour
1 teaspoon salt
1 teaspoon baking powder
1/2 teaspoon baking soda
2 teaspoons vanilla
1 cup buttermilk or sour milk at room temperature
1/4 cup water
3 tablespoons rum (or flavoring) adjust as desired (I use Bacardi)
confectioner's sugar

Preheat oven to 325 degrees. Cover bottom of 10 inch spring form pan with foil and spray all over with Pam or nonstick spray. In large mixing bowl, cream one cup butter, gradually add 2 cups sugar, beating until light and fluffy. Add eggs, one at a time, beating well after each. Add flour, salt, baking powder, baking soda, buttermilk, and vanilla. Blend on low speed until batter is moist, scrape sides of bowl, beat on medium speed for 2 minutes. Pour batter into spring form pan. Bake for 72 minutes (for a 10 inch pan). Before the end of cook time, prepare butter sauce by combining 1 cup sugar, water, and 1/2 cup butter. Heat on low until butter melts, add rum and cook until rolling boil begins. Immediately after removing cake from oven, prick cake all over with large fork. Pour hot butter sauce very slowly over hot cake. Cool cake completely, then cover top of cake with plastic wrap and invert onto flat plate. Remove spring form pan and invert again onto cake plate. Remove plastic wrap. Sprinkle with confectioner's sugar just before serving. This cake freezes well.