Pineapple Upside Down Pound Cake

or 3/4 stick) butter (salted is fine here)

packed dark brown sugar

heavy pinch of salt if using unsalted butter; wee pinch if using salted butter

about 6-8 oz chopped pineapple ((fresh or canned in juice))

unsalted butter

granulated sugar

best quality vanilla

gently rounded teaspoon sea salt

eggs (, beaten)

cake flour

baking powder

chopped pineapple ((fresh or canned in juice))

sour cream