if one is willing to make simple efforts like adding water and an egg, it's not much of a stretch to start with
flour
pinch of salt
baking powder
granulated sugar
I use egg whisked into the milk, or buttermilk.
powdered buttermilk is also available
or use faux buttermilk
or use real buttermilk.
flavoring adds
vanilla extract
almond extract
peppermint extract
rum flavor
other adds
blueberries
banana
strawberries
pecans
the home made mix is always fresh, no 'funny tastes' from preservatives/flow agents/etc/etc.
note: using buttermilk, after opening the container of powdered buttermilk, transfer it to a glass jar with tight lid - it will turned into a rock in about 2 weeks if left in the original container.