Preheat oven to 350 and line a 8×8 pan with parchment paper, set a side.
In a medium sauce pan add the first 6 ingredients (butter, brown sugar, chopped chocolate, cocoa powder, salt and vanilla extract) heat just until all ingredients are melted and smooth.
Remove from heat and allow mixture to cool 5 minutes. Add eggs, one at a time, whisk quickly until fully incorporated. Do the same with the almond flour.
Stir in chocolate chips and walnuts. Bake for 30 minutes.