Preheat the oven to 350 °F and line an 8 by 8 inch square baking pan with parchment paper.

Make the cookie layer: In a large bowl, whisk together 1 1/3 cups almond flour, 1/3 cup sweetener, baking soda, and salt.

Add 1/4 cup softened butter to the dry ingredients and stir until the mixture looks evenly moistened and slightly sandy.

Add the egg and vanilla bean paste to the bowl and stir until a thick, smooth dough forms.

Fold in 1/3 cup sugar free chocolate chips until evenly distributed.

Spoon about 2/3 of the cookie dough into the prepared pan and use lightly wet fingers to press it into an even layer over the bottom of the pan.

Make the brownie layer: In a clean bowl, stir together 2/3 cup almond flour, 1/2 cup sweetener, cocoa powder, and baking powder.

Add 3 tablespoons softened butter and mix until a thick, cohesive batter forms; it will be slightly looser than the cookie dough.

Fold in 3 tablespoons sugar free chocolate chips.

Gently dollop the brownie batter over the pressed cookie layer, then use the back of a spoon or an offset spatula to spread it into an even layer without pressing into the cookie base.

Bake for 25 to 30 minutes, until the top is set, the edges look slightly dry, and the center no longer jiggles when you nudge the pan.

Place the pan on a cooling rack and let the brookies cool completely in the pan, then lift out using the parchment and slice into 16 squares.