You will be the hero of brunch for whipping up this light and crumbly coffee cake, topped with a decadent cinnamon crumble. Even better, it only takes about 5 minutes of hands on prep, and then 20 minutes in the oven!
Mix sugar, egg, butter, milk, flour and baking powder together in a large mixing bowl. This will make a very stiff batter.
Pour the batter into a lightly greased 9x13'' baking pan.
Dot the top of the cake with the butter pieces. Spread evenly.
Sprinkle the top of the batter with brown sugar, and then with cinnamon. I typically eyeball the cinnamon, so you can adjust the amount to your tastes.