DEAR MISS MANNERS: For about a decade, my partner and I have made homemade packages of treats for about a dozen households at holiday time. These have varied slightly over the years, but usually include nuts, candies and baked goods. Sometimes a cake, some brownies or cookies. This year, I used a different flour that included the salt and baking powder, saving some time on measuring ingredients. I am the first to admit that this product worked fine for the cake, but made the cookies a little less tasty somehow. We mailed them all out anyway, as we thought the difference was negligible. Apparen…