Sift together flour, cardamom, baking powder, and salt.
Beat butter and eggs in a large bowl, then gradually add in the sugar.
Add in vanilla and pineapple slices (very finely chopped or pureed - this adds to the sweetness and moistness of the cake).
Mix in cardamom, baking powder and vanilla essence.
Add the whole wheat flour slowly and fold gently until a smooth batter is formed.