Preheat the oven to 350F. Line an 8X8" square baking pan with baking parchment.

Add butter and sweetener to a stand mixer bowl and cream them together.

Add the remaining brownie ingredients and beat until thoroughly combined.

Spoon the mixture into the baking pan and bake for 10 minutes.

Meanwhile, beat together the cheesecake ingredients until smooth. Once the brownie layer has pre-baked, spoon the cheesecake layer over the top and bake for a further 20 minutes or until the top layer has cooked through.

Let cool slightly then cut into 9 squares.