Pre-heat oven to 350*F.
In a medium bowl, mix together your almond flour, cocoa powder, arrowroot starch, espresso powder, xanthan gum, baking powder and salt. Set aside.
In another larger bowl, whisk together your melted butter, eggs, vanilla extract and sweeteners until smooth. Set aside.
In a microwavable bowl, melt your chocolate-chips and 1/2 tbsp butter in 30s increments, stirring each time until completely melted and smooth.
Pour your melted chocolate into the butter and egg mixture and stir until combined.
Add your dry ingredients and stir again until everything is combined and the batter becomes thick.
Stir in an extra 1/4 cup of chocolate chips (optional).
Line an 8x8 inch pan with parchment paper and press about 2/3 of your mixture evenly into the pan using a spatula or your hands to help.
Pour the peanut butter filling over the brownie layer and use a spatula to even it out.
Top the peanut butter layer with the remaining brownie batter by flattening chunks with your hands and then placing them/crumbling them on top.
Bake for 18-20min. The peanut butter. brownies will still be quite soft but the centre shouldn't jiggle when you shake the pan. Don't over-bake!
Let the brownies cool completely before lifting them from the pan. Slice into squares and serve! Enjoy The Best Low Carb Keto Brownies! (*Pro tip: these are great with a scoop of low carb ice cream or homemade sugar free whipped cream!)