Melt 1 stick of butter in a large microwaveable bowl.
Stir in sugar until combined
Stir in cocoa powder, vanilla, baking powder and salt.
Add the eggs and beat until smooth
Add the flour and mix until just combined.
Spread brownie batter into prepared baking pan. Smooth with a spatula.
Spread pumpkin cheesecake batter over the top of brownie batter. Smooth with a spatula.
Sprinkle crumb topping evenly over the top of pumpkin cheesecake layer.
Bake for 40-50 minutes until a toothpick inserted into pumpkin cheesecake layer comes out clean.
Let cool completely. Cut into squares and serve with caramel sauce.