Preheat the oven to 350 degrees F and spray an 8X8 baking dish with a non-stick cooking spray.
In a small bowl, whisk together the flour, baking powder, baking soda and salt. Set aside.
In a large mixing bowl, beat together the butter and granulated sugar until light and fluffy. Mix in the ground cinnamon.
Add in the eggs, one at a time until combined and light and fluffy.
Mix in the sour cream and vanilla extract.
Hand stir in the flour, baking powder, salt, sour cream, vegetable oil and vanilla extract until combined and smooth.
Slowly add in the dry ingredients and milk, rotating between each one, until just combined.
In a small bowl, whisk together the topping ingredients.
Pour half of the batter evenly into the prepared pan. Sprinkle half of the cinnamon and sugar mixture on top.
Top with the remaining cake batter and remaining cinnamon and sugar mixture.
Bake for 25-30 minutes until the cake is fully set, the edges on the cake begin to brown and a toothpick inserted into the center of the cake comes out clean.
Allow the cake to cool for 10-15 minutes and then it’s ready to slice, serve and enjoy!