Preheat the oven to 350°F (175°C) and grease your baking pan.
In one bowl, whisk together flour, baking powder, baking soda, and salt.
In another bowl, cream together sugar, butter, milk, vanilla, and apple cider vinegar.
Add the wet ingredients to the dry ingredients and mix until smooth.
For the streusel topping, combine sugar, flour, cinnamon, and butter until crumbly.
Pour the batter into the prepared pan and sprinkle the streusel topping evenly over it.
Bake for 30-35 minutes or until a toothpick comes out clean.
Let the cake cool for 10 minutes, slice, and serve.