Preheat oven to 325°F (160°C).

Grease two 9x13-inch pans (or one 9x13-inch and two 8x8-inch square pans).

In a large mixing bowl, cream together the softened butter, sugar, and vanilla until smooth and creamy.

In a separate bowl, whisk together the flour, cornmeal, salt, cornstarch, and baking powder.

Gradually add the dry ingredients to the butter mixture, alternating with the eggs. Begin and end with the dry ingredients.

Mix well after each addition, ensuring the batter remains smooth and creamy.

Stir in the lemon juice (or rum) and raisins.

Pour the batter into the prepared pans, filling them about 2/3 full.

Bake for 60 minutes, or until a toothpick inserted into the center comes out clean.