1Combine half a cup of brown sugar and one teaspoon of cinnamon.
2To make the streusel, lightly mix one cup of flour, one cup of brown sugar, half a teaspoon of kosher salt, four teaspoons of cinnamon, and half a cup of cooled melted butter with a fork.
3Cream together half a cup of softened butter with one cup of sugar.
4Add two eggs and some vanilla and mix.
5Add two cups of flour, half a teaspoon of kosher salt, one teaspoon of baking powder, and one teaspoon of baking soda.
6Mix together one cup of sour cream and half a cup of buttermilk.
7Add the sour cream and buttermilk mixture to the batter and mix everything until well combined.
8Spread half the batter in a lined baking tray.
9Sprinkle the cinnamon sugar over the batter.
10Add the rest of the batter and top it with the streusel.