Line a 9X13 baking dish with parchment paper and spray the paper with a non-stick cooking spray.
In a large mixing bowl, beat together softened unsalted butter, brown sugar, and granulated sugar with a hand mixer or stand mixer until light and fluffy.
Add eggs and vanilla extract. Mix until well combined.
In a separate bowl, whisk together all-purpose flour, baking powder, ground cinnamon, and salt.
Gradually stir the dry ingredients into the butter mixture until just combined. Do not overmix.
Press this mixture into an even layer in the baking dish. In a small bowl, stir together granulated sugar and ground cinnamon for the topping.
Bake for 25-30 minutes until a toothpick inserted into the center comes out clean.
Allow to cool completely and then cut and enjoy!
Notes
Store the leftovers in an airtight container for up to 4-5 days.