Combine dry ingredients in a bowl, stir well and set aside.
Combine milk and vinegar, stir and set aside.
In another bowl, beat butter and sugar together. Add molasses and egg and beat until fluffy.
Add milk mixture to butter and sugar mixture and beat well. (As you mix the texture could change or separate. Don't panic – that's just chemistry, everything will turn out fine.)
Add dry ingredients to the wet in approximately 3 parts. Mix well.
Add raisins and stir to distribute them evenly through the batter.
Drop by teaspoonfuls on parchment lined cookie sheet. Bake for 10 – 12 minutes or ntil nice and puffy and edges turn a bit brown. Cool on rack.