Preheat the oven to 350°F (175°C). Line an 8x8-inch baking pan with parchment paper, leaving an overhang on two sides for easy removal.
In a large bowl, whisk together the almond flour, cocoa powder, granulated erythritol, baking powder, and salt.
Add the melted butter, eggs, and vanilla extract to the dry ingredients. Stir until a thick, smooth brownie batter forms.
In a separate bowl, beat the softened cream cheese with powdered erythritol, egg, and vanilla until smooth and creamy.
Spread the brownie batter evenly into the prepared pan. Dollop spoonfuls of the cream cheese mixture on top.
Use a toothpick or the tip of a small spoon to swirl the cream cheese into the brownie batter, creating a marbled pattern. Be careful not to over-swirl.
Bake for 28-32 minutes until the edges are set and the center is just barely jiggly. Let cool completely in the pan before lifting out and slicing into 16 squares.
