Preheat oven to 350F. Grease a 9-inch tube pan and set it aside.
In a large bowl or a KitchenAid mixer, beat butter and sugar together until light and creamy.
Add eggs, one at a time.
In a different bowl, sift together dry ingredients and add them to the butter, alternatively with milk and vanilla. If you choose to add raisins, add them now.
Pour batter into the greased tube pan.
Mix the topping in a smaller bowl. Add it to the top of the batter.
Take a wooden skewer or knife and swirl the batter to slightly mix the topping in.
Bake at 350F for about an hour. Remove from the oven and allow it to cool for about 10 minutes before removing from the pan.