Preheat oven to 350°F (175°C). Line an 8×8-inch baking pan with parchment paper, leaving overhang on two sides.
In a medium bowl, whisk almond flour, cocoa powder, granulated erythritol, salt, and baking powder.
In a large bowl, whisk together melted butter, eggs, and vanilla extract until smooth.
Gradually fold dry ingredients into the wet mixture in batches, mixing just until combined.
In a separate bowl, beat softened cream cheese until smooth. Mix in powdered erythritol until fully incorporated.
Spread two-thirds of brownie batter evenly into prepared pan.
Carefully spread cheesecake mixture over the brownie layer to the edges.
Drop spoonfuls of the remaining brownie batter over cheesecake layer. Use a knife to create gentle swirls.
Bake for 25–30 minutes, until edges are set and the center is slightly jiggly.
Cool completely in pan on a wire rack. Then refrigerate for at least 2 hours or overnight before slicing and serving.