1. Grease and flour one 8 or 9 inch tube pan (you may also use a 9x5 inch loaf pan).
2. Preheat oven to 325 degrees F.
3. Sift the flour, baking soda, salt, baking powder (optional), vanilla powder (if you are using powder instead of extract) together, set aside.
4. In a large bowl, cream butter and sugar. Mix in the eggs, one at time and beating well after each addition.
5. Stir in the vanilla extract (if you are using the extract) and ground cardamom (optional).
6. Gently mix in flour mixture alternately with the buttermilk, starting and ending with the flour mixture (either use whisk or set the beater on low).
7. Toss the raisin with 1/2 tablespoon flour. Gently mix in raisin mixture. (optional).
8. Pour batter into the prepared pan. Bake in preheated oven for about 75 minutes. Do not open oven door until after an hour. The cake is ready when it begins to pull away from the side of the pan. Let cool in pan for 10 minutes. Turn out onto a wire rack and cool completely.